Method for manufacturing liquid crystal display device, substrate for liquid crystal display device, method for manufacturing substrate for liquid crystal display device, and spacer particle dispersion

ABSTRACT

In accordance with the present invention, it is possible to provide the method for manufacturing a liquid crystal display, a substrate for liquid crystal display, a method for manufacturing the substrate for a liquid crystal display, and the dispersion of spacer particles, in which a spacer particle can be precisely located at an arbitrary position on a substrate by an ink-jet method.  
     The present invention relates to a method for manufacturing a liquid crystal display, wherein spacer particles are located at an arbitrary position on a substrate by ejecting a dispersion of spacer particles by an ink-jet method, a diameter D 1  of an adhered droplet of said dispersion of spacer particles, having adhered to said substrate, and a diameter D 2  of the adhering spacer particles, remaining after the said dispersion of spacer particles is evaporated, satisfying a relationship of Equation (1). 
 
 D   2 &lt;( D   1 ×0.5)  (1)

TECHNICAL FIELD

The present invention relates to a method for manufacturing a liquidcrystal display, a substrate for a liquid crystal display, a method formanufacturing a substrate for a liquid crystal display, and a dispersionof spacer particles, in which a spacer particle can be precisely locatedat an arbitrary position on a substrate by an ink-jet method.

BACKGROUND ART

Currently, a liquid crystal display is widely used to personalcomputers, portable electronics and the like.

FIG. 1 is a sectional view showing an example of a liquid crystaldisplay. As shown in FIG. 1, generally, a liquid crystal display has aconstitution in which two transparent substrates 1, respectively, onwhich a transparent electrode 3, an orientation layer 8, a color filter4 and a black matrix 5 are located inside and a polarizer 2 is locatedoutside, are located on opposed sides through a sealing material 9installed at the peripheral, and liquid crystal 6 is filled into a gapformed and sealed. And, the transparent substrate 1 is further dividedinto a pixel area to be a display section provided with a pixelelectrode and a shading area not provided with a pixel electrode. Inthis liquid crystal display, spacer particles 7 are used for the purposeof regulating a spacing of two transparent substrates 1 and maintaininga proper thickness (cell gap) of a liquid crystal layer.

As a method for locating the spacer particle 7, conventionally, therehas been used a method for spraying the spacer particles in a randomfashion and uniformly on a substrate provided with a pixel electrode.However, in this method, the spacer particles are located also on apixel electrode, namely, a display section of a liquid crystal display.Generally, since a spacer particle is made of synthetic resin or glass,when a spacer is located on a pixel electrode, there was a problem thata so-called depolarization phenomenon, in which polarized light isdisturbed and loses a polarization property, arose and therefore thespacer portion causes light leakage, or orientation of liquid crystal onthe spacer surface is disturbed to cause light leakage and displayquality might deteriorate because of degradation of contrast and colortone. Particularly, in a TFT liquid crystal display, a serious problemthat a TFT device was damaged when pressure was applied to a substratemight arise.

For this problem, attempt has been made to overcome such a problem bylocating the spacer particle on an area other than a pixel area which isa display section of a transparent substrate, namely, only in a shadingarea. For example in Japanese Kokai Publication Hei-4-198919, there isdisclosed a method in which after an opening of a mask having an openingand a shading area are oriented, the spacer particles are located onlyat the opening. And, in Japanese Kokai Publication Hei-6-258647, thereis disclosed a method in which after allowing a photosensitive materialto adsorb spacer particles electrostatically, the spacer particles aretransferred to a transparent substrate. However, in these methods, sinceit is necessary to bring a mask or a photosensitive material intocontact directly with a substrate, there was a problem that anorientation layer on a substrate might be damaged to cause thedegradation of display quality.

And, in Japanese Kokai Publication Hei-10-339878, there is disclosed amethod in which by spraying charged spacer particles on an pixelelectrode, to which the voltage of the same polarity is applied, on asubstrate, spacer particles are located on a shading area by virtue ofelectrostatic repulsive force. However, in this method, there was aproblem that because an electrode, which has a configuration along apattern to be located, is required, it is impossible to completelylocate the spacer particles at arbitrary position and a liquid crystaldisplay of type which this method is applicable to was limited.

On the other hand, in Japanese Kokai Publication Sho-57-58124, there isdisclosed a method for locating a dispersion of spacer particles on asubstrate using an ink-jet printer. Since in this method, it waspossible to locate a spacer without directly contacting a substrate inany position and in any pattern, this method was considered to beextremely effective. However, in recent years, as more precise,downsized and diversified electronic equipment has been developed, highperformances such as a display downsized and having high contrast havebeen also required for a liquid crystal display. Therefore, a width of ashading area on which spacer particles are located becomes about 10 to30 μm, and in order to locate the spacer particles selectively on such anarrow area, an extremely high ejection accuracy of an ink-jet systemhas been required and in addition several problems have arisen.

The first problem is that it is impossible to control a size of adroplet ejected by a ink-jet method so as to be smaller than a size ofarea on which spacers are to be located. Generally, a diameter of adroplet having adhered after a droplet ejected by a ink-jet method hasadhered to the substrate is about 40 to 200 μm. When a droplet size isfurther reduced, a diameter of a nozzle hole must be reduced, but sincethe diameter of a nozzle hole of a current ink-jet system is about 20 μmat the lowest and a particle diameter of the spacer particle is about 2to 10 μm, further smaller nozzle hole diameter will result in cloggingof a nozzle or unstable ejection.

As one method for accommodating the droplet ejected by a ink-jet methodin a predetermined section (position) accurately, there is studied amethod for controlling a wetting property of a predetermined section ofa surface receiving the ejection of a droplet with respect to a droplet.For example, as a ejection liquid of a ink-jet system, an aqueoussolution is frequently used, but such an aqueous solution has acharacteristic of spreading over a high polar surface receiving theejection of a droplet, such as a metal surface, with the high polarsurface receiving the ejection of a droplet wetted, but not spreadingover a low polar surface receiving the ejection of a droplet, such as aresin surface, with the low polar surface receiving the ejection of adroplet wetted.

As an example of utilizing such a characteristic, for example inJapanese Kokai Publication Hei-6-347637, there is disclosed a method forusing a corresponding ink having a color only in a specified pixel areaon a substrate provided with a pixel area and a shading area as a colorfilter of a liquid crystal display is manufactured. In this method, awater repellent section is formed in a shading area on the substrate bya photoresist method, and it is considered that this method can beapplied similarly to the case where the spacer particle is located usinga ink-jet system. On the substrate of a liquid crystal display, theso-called orientation layer, for example, a polyimide resin film isgenerally formed in order to regulate an orientation state of liquidcrystal and the spacer particles are located on this orientation layer.When the spacer particles are located on the substrate by a methoddisclosed in Japanese Kokai Publication Hei-6-347637, it is thought, forexample, that a coat of photosensitive alkali-soluble resin such as anacrylic acid copolymer and the like is formed on the orientation layer,and by applying photolithography treatment to the coated orientationlayer, only the surface of the orientation layer in the position atwhich the spacer particle is chosen to be located, is brought into ahigh polar state. However, actually, a rubbing process by nylon or rayonis applied to the surface of the orientation layer in order to regulatethe direction of orientation of liquid crystal and it is extremelydifficult to apply photolithography treatment to the surface of theorientation layer, thus processed precisely. Further, since the highpolar coat exists in convex form on the orientation layer, when the highpolar coat is partially formed and then the rubbing process is applied,the high polar coat on the surface of the orientation layer, which isessentially low in adhesion, will peels off and therefore it becomesimpossible to locate the spacer particles selectively in thepredetermined section. Thus, in actuality, it was technologicallydifficult to a considerable degree to form an area having the polaritydiffering from a coat of the orientation layer on the coat of theorientation layer, which needs a special state of the surface.

The second problem is the dispersibility of the spacer particle in thedispersion of spacer particles. In a piezo ink-jet system which issuitably used for ejecting the dispersion of spacer particles in severalkinds of ink-jet systems, it is said that the surface tension of liquidejected is favorably 25 to 55 mN/m. But, since the conventional spacerparticles are generally premised on being dispersed in the medium havinga surface tension of 30 mN/m or less such as lower alcohols, Freon orwater, they are hard to be dispersed in a medium having a relativelyhigh surface tension, which is suitable for ink-jet. In Japanese KokaiPublication 2000-347191, there is disclosed a method for coating thesurface of spacer particle with a hydrophobic compound using theadsorption effect of the spacer particle, but it is difficult todisperse even such a coated particle in the form of complete singleparticle in a medium having a high surface tension. And, since aparticle with a hydrophobic surface has a low affinity for theorientation layer on the substrate, the adhesion thereof is notsufficient and the located spacer particle may move within a liquidcrystal cell due to an impact to damage the orientation layer. Further,there is a problem that by a coating technique based on an adsorptioneffect, it is difficult to fix completely a hydrophobic compound on thesurface of the spacer particle, and therefore a part of the hydrophobiccompound is eluted into ink during storage and when this elution isejected with ink on the substrate, it covers the orientation layer, orthe hydrophobic compound is eluted in liquid crystal in a liquid crystalcell, leading to a defect of display quality of the liquid crystaldisplay. Further, it is necessary to prevent light leakage due toabnormal orientation of liquid crystal around the spacer particle whichhas overrun on the pixels, but introduction of a hydrophobic functionalgroup, which is known to function effectively for controlling theabnormal orientation of liquid crystal, is opposed to dispersing thespacer particle in the form of single particle in the medium for ink-jetink. Thus, properties required for the spacer particle are verycomplicated and currently it has been difficult to satisfy allrequirements while maintaining excellent dispersibility.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method formanufacturing a liquid crystal display, a substrate for a liquid crystaldisplay, a method for manufacturing a substrate for a liquid crystaldisplay, and a dispersion of spacer particles, in which a spacerparticle can be precisely located at an arbitrary position on asubstrate by an ink-jet method.

A first aspect of the present invention pertains to a method formanufacturing a liquid crystal display, wherein spacer particles arelocated at an arbitrary position on a substrate by ejecting a dispersionof spacer particles by an ink-jet method, a diameter D₁ of an adhereddroplet of said dispersion of spacer particles, having adhered to saidsubstrate, and a diameter D₂ of the adhering spacer particles, remainingafter the said dispersion of spacer particles is evaporated, satisfyinga relationship of Equation (1).D ₂<(D ₁×0.5)  (1)

In the method for manufacturing a liquid crystal display according tothe first aspect of the present invention, it is preferred that thesurface temperature of a substrate at the time when a dispersion ofspacer particles adheres to the substrate is at least 20° C. lower thana boiling point of a liquid having the lowest boiling point amongliquids contained in said dispersion of spacer particles, and it ispreferred that the surface temperature of a substrate at the time when adispersion of spacer particles adheres to the substrate is at least 20°C. lower than a boiling point of a liquid having the lowest boilingpoint among liquids contained in said dispersion of spacer particles,and the surface temperature of a substrate is 90° C. or less during atime period until the dispersion of spacer particles is completelyevaporated. And, it is preferred that the above-mentioned dispersion ofspacer particles comprises a medium containing a liquid having a boilingpoint of less than 100° C. in an amount of 10 to 80% by weight andspacer particles, and the content of said spacer particle is 0.05 to 5%by weight, and it is preferred that the above dispersion of spacerparticles comprises a medium containing a liquid having a boiling pointof less than 100° C. in an amount of 10 to 80% by weight and a liquidhaving a boiling point of 150° C. or more in an amount of 80 to 10% byweight, and spacer particles, and the content of said spacer particle is0.05 to 5% by weight. Further, the above-mentioned dispersion of spacerparticles preferably has a contact angle of 25 to 70° relative to anorientation layer on a substrate.

A second aspect of the present invention pertains to a substrate for aliquid crystal display, wherein a color filter comprising a pixel areaarrayed in accordance with a given pattern and a shading area definingsaid pixel area is formed, an orientation layer, a contact angle ofwhich relative to the dispersion of spacer particles is θb, beingpresent in an area representing said pixel area and, an area, a contactangle of which relative to the dispersion of spacer particles is θa,being present at least in a part of an area representing said shadingarea, and said θa and said θb satisfying a relationship expressed byEquation (2).θa<θb  (2)

Also, a method for manufacturing the substrate for a liquid crystaldisplay according to a second aspect of the present invention, whereinafter an orientation layer, a contact angle of which relative to thedispersion of spacer particles is θb, is uniformly formed on the wholesurface of a substrate, by applying non-contact energy irradiation to aposition at which the spacer particle is chosen to be locate, theorientation layer in the position is removed or modified to bring acontact angle relative to the dispersion of spacer particles into θa,constitutes the present invention.

A method for manufacturing the substrate for a liquid crystal displayaccording to the second aspect of the present invention, wherein aphotosensitive polyimide resin precursor or a photosensitive polyimideresin is uniformly applied to a substrate having a surface, a contactangle of which relative to the dispersion of spacer particles is θa, andby exposing the photosensitive polyimide film via the medium of a maskand developing the film, an orientation layer comprising polyimide resinis formed in the form of a pattern on the surface of the substrate otherthan the position at which the spacer particle is chosen to be locateand a contact angle of the surface of said orientation layer relative tothe dispersion of spacer particles is brought into θb, also constitutesthe present invention.

A method for manufacturing a liquid crystal display using the substratefor a liquid crystal display according to the second aspect of thepresent invention, wherein the dispersion of spacer particles is ejectedonto the area where a contact angle of said substrate for a liquidcrystal display relative to the dispersion of spacer particles is θa tolocate the spacer particles, also constitutes the present invention.

A third aspect of the present invention pertains to a dispersion ofspacer particles, which comprises spacer particles in which avinyl-based thermoplastic resin, formed by free radical polymerizingvinyl-based monomers having a hydrophilic functional group and/or analkyl group having 3 to 22 carbon atoms, is combined with the surface ofan inorganic fine particle and/or an organic fine particle by graftpolymerization; and a medium comprising water and/or a hydrophilicorganic solvent and having the surface tension of 25 to 50 mN/m at 20°C., said spacer particles being dispersed in the form of a singleparticle in said medium. The above-mentioned vinyl-based monomerpreferably contains a vinyl-based monomer having a hydrophilicfunctional group in an amount of 30 to 80% by weight and a vinyl-basedmonomer having an alkyl group having 3 to 22 carbon atoms in an amountof 20 to 60% by weight. And, the above-mentioned hydrophilic functionalgroup is preferably at least one species selected from the groupconsisting of hydroxyl group, carboxyl group, sulfonyl group, phosphonylgroup, amino group, amide group, ether group, thiol group and thioethergroup.

BRIEF DESCRIPTION OF THE DRAWING(S)

FIG. 1 is a sectional view showing an example of a liquid crystaldisplay. FIG. 2 is a schematic view showing a position, where a spacerparticle is located, on a substrate used in Examples 7 and 8. In thesedrawings, 1 indicates a transparent substrate, 2 indicates a polarizer,3 indicates a transparent electrode, 4 indicates a color filter, 5indicates a black matrix, 6 indicates liquid crystal, 7 indicates spacerparticle, 8 indicates an orientation layer and 9 indicates a sealingmaterial.

DETAILED DISCLOSURE OF THE INVENTION

Hereinafter, the present invention will be described in detail.

The first aspect of the present invention pertains to a method formanufacturing a liquid crystal display, wherein spacer particles arelocated at an arbitrary position on a substrate by ejecting a dispersionof spacer particles by an ink-jet method, a diameter D₁ of an adhereddroplet of said dispersion of spacer particles, having adhered to saidsubstrate, and a diameter D₂ of the adhering spacer particles, remainingafter the said dispersion of spacer particles is evaporated, satisfyinga relationship of Equation (1).D ₂<(D ₁×0.5)  (1)

This means that after the dispersion of spacer particles has adhered tothe substrate, the spacer particles in the dispersion of spacerparticles gather in the vicinity of a central portion of the dropletadhering in an evaporating process of the dispersion. Thus, by ejectingthe dispersion of spacer particles as liquid droplets having a dropletdiameter which can be formed and ejected by the ink-jet method by theink-jet method, it becomes possible to locate spacer particles in asmaller area than a liquid droplet diameter.

As a result of an intense study, the present inventors have found thatthe use of a dispersion of spacer particles having a given property andthe conduct of a drying process under given conditions after adhering tothe substrate allow the diameter D₁ of the adhered droplet of thedispersion of spacer particles having adhered to the substrate and thediameter D₂ of the adhering spacer particles remaining after thedispersion of spacer particles is evaporated to satisfy a relationshipof the above equation (1), and have reached the completion of the firstaspect of the present invention.

Further, in this specification, the diameter of the droplet havingadhered of the dispersion of spacer particles refers to an outsidediameter of a liquid droplet of the dispersion of spacer particleshaving adhered to the substrate, and the diameter of the adhering spacerparticles refers to an outside diameter of an area which the spacerparticles, remaining on the substrate in evaporating the dispersion ofspacer particles is, adhere to.

The above-mentioned dispersion of spacer particles comprises spacerparticles and a medium. The above-mentioned spacer particle is notparticularly limited and for example, a particle formed from aninorganic material such as silica and a particle formed from an organicmaterial such as resin are given. Among others, a spacer particle formedfrom resin is preferred in that it has adequate hardness not to damagean orientation layer formed on a substrate of a liquid crystal displayand is easy to follow the change in thickness due to thermal expansionor thermal contraction of the orientation layer, and further isrelatively less in move within a cell.

The above-mentioned resin composing the spacer particle can be obtainedby polymerizing a monofunctional monomer and/or a polyfunctionalmonomer. Among others, a copolymer of a monofunctional monomer and apolyfunctional monomer is suitable from the viewpoint of strength. Inthis case, the portion of the above-mentioned polyfunctional monomer ispreferably 50% by weight or less. More preferably, it is 30% by weightor less.

The above-mentioned monofunctional monomer is not particularly limitedand includes, for example, styrene derivatives such as styrene,α-methylstyrene, p-methylstyrene, p-chlorostyrene andchloromethylstyrene; vinyl esters such as vinyl chloride, vinyl acetateand vinyl propionate; unsaturated nitriles such as acrylonitrile;(meth)acrylate ester derivatives such as methyl (meth)acrylate, ethyl(meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,stearyle (meth)acrylate, ethylene glycol (meth)acrylate, trifluoroethyl(meth)acrylate, pentafluoropropyl (meth)acrylate and cyclohexyl(meth)acrylate. These monofunctional monomers may be used alone or maybe used in combination of two or more species.

The above-mentioned polyfunctional monomer is not particularly limitedand includes, for example, divinylbenzene, 1,6-hexanedioldi(meth)acrylate, trimethylolpropane tri(meth)acrylate,tetramethylolmethane tri(meth)acrylate, tetramethylolpropanetetra(meth)acrylate, diallyl phthalate and isomer thereof, triallylisocyanurate and derivatives thereof, trimethylolpropanetri(meth)acrylate and derivatives thereof, pentaerythritoltri(meth)acrylate, pentaerythritol tetra(meth)acrylate,dipentaerythritol hexa(meth)acrylate, polyethylene glycoldi(meth)acrylate of ethylene glycol di(meth)acrylate, polypropyleneglycol di(meth)acrylate of propylene glycol di(meth)acrylate,polytetramethylene glycol di(meth)acrylate, neopentyl glycoldi(meth)acrylate, 1,3-butylene glycol di(meth)acrylate,2,2-bis[4-(methacryloxypolyethoxy)phenyl]propane di(meth)acrylate of2,2-bis[4-(methacryloxyethoxy)phenyl]propane di(meth)acrylate,2,2-hydrogenated bis[4-(acryloxypolyethoxy)phenyl]propanedi(meth)acrylate and 2,2-bis[4-(acryloxyethoxypolypropoxy)phenyl]propanedi(meth)acrylate. These polyfunctional monomers may be used alone or maybe used in combination of two or more species.

An initiator is used in the above polymerization. The above-mentionedinitiator is not particularly limited and for example, organic peroxidessuch as benzoyl peroxide, lauroyl peroxide, o-chlorobenzoyl peroxide,o-methoxybenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide andt-butylperoxy-2-ethylhexanoate and di-t-butyl peroxide; and azocompounds such as azobis(isobutyronitrile),azobis(cyclohexacarbonitrile) and azobis(2,4-dimethylvaleronitrile) aregiven. Preferably, an amount of the above initiator to be used isusually 0.1 to 10 parts by weight per 100 parts by weight of apolymerizable monomer.

A method for producing spacer particles by polymerizing theabove-mentioned monomer is not particularly limited and for example,suspension polymerization, seed polymerization, and dispersionpolymerization are given.

The above-mentioned suspension polymerization is a method, in which amonomer composition comprising a polymerizable monomer and an initiatoris dispersed in a poor solvent so as to give an intended particlediameter and polymerized. According to the above suspensionpolymerization, since polydisperse particles having a relatively wideparticle size distribution can be obtained, it is possible to producethe spacer particle including a wide variety of particle diameter byconducting a classification operation.

As a disperse medium used for the above suspension polymerization, thereis usually used a substance formed by adding a disperse stabilizer towater. As the above-mentioned disperse stabilizer, there are givenpolymers soluble in a medium such as polyvinyl alcohol,polyvinylpyrrolidone, methyl cellulose, ethyl cellulose, polyacrylicacid, polyacrylamide and poly(ethylene oxide). And, a noionic or ionicsurfactant is also appropriately used. The conditions of polymerizationof the above-mentioned suspension polymerization vary with species ofthe initiator and the polymerizable monomer, but usually, suitably,polymerization temperature is 50 to 80° C. and polymerization time is 3to 24 hours.

The above-mentioned seed polymerization is a method in which by allowingthe monodisperse seed particle synthesized by soap-free polymerizationor emulsion polymerization to absorb further a polymerizable monomer andpolymerizing this seed particle, a particle diameter of the particle isexpanded to a predetermined diameter. According to the seedpolymerization, since monodisperse particles can be obtained withoutconducting a classification operation, it is possible to produce thespacer particle having a specified particle diameter in large quantity.An organic monomer used in the above seed particle is not particularlylimited, but as for the material of the seed particle, it is preferredto use a substance having components close to that of a monomer inconducting seed polymerization in order to inhibit phase separation. Forexample, a styrene-based monomer is preferred for an aromatic divinylmonomer and an acrylic monomer is preferred for an acrylic multivinylmonomer. Since a particle size distribution of the seed particle isreflected on a particle size distribution after seed polymerization, itis preferably as monodisperse as possible and CV value is preferably 5%or less.

And, in seed polymerization, a disperse stabilizer may also be used asrequired. As such a disperse stabilizer, polymers soluble in a mediumare suitable, and for example, polyvinyl alcohol, polyvinylpyrrolidone,methyl cellulose, ethyl cellulose, polyacrylic acid, polyacrylamide andpoly(ethylene oxide) are given. And, a nonionic or ionic surfactant isalso appropriately used.

In seed polymerization, it is preferred to add 20 to 100 parts by weightof a polymerizable monomer per 1 parts by weight of seed particles. Whenthe addition amount is less than 20 parts by weight, the strength of thespacer particle to be obtained may become insufficient, and when it ismore than 100 parts by weight, a particle size distribution may widendue to particle cohesion during seed polymerization.

The above-mentioned dispersion polymerization is a method, in which byconducting polymerization in a poor solvent system which dissolves apolymerizable monomer but does not dissolve a resin produced and addinga polymer-based disperse stabilizer to this system, a produced polymeris precipitated in the form of particle. According to the dispersionpolymerization, since monodisperse particles can be obtained withoutconducting a classification operation, it is possible to produce thespacer particle having a specified particle diameter in large quantity.

In dispersion polymerization, generally, when a polyfunctional monomeris used, the cohesion of the resulting particle is apt to occur and itis difficult to obtain monodisperse crosslinked particles stably, but itbecomes possible to polymerize a monomer containing a crosslinkedcomponent by selecting conditions. However, from the viewpoint ofcohesion during polymerization or strength, the portion of thepolyfunctional monomer is preferably 50% by weight or more with respectto the total monomers. When this portion is less than 50% by weight,since the surface of fine particle formed during polymerization is softin the medium, impingement between the fine particles causes cohesionand therefore a particle size distribution widens, and further this mayresult in cohesion body. And, even though monodispersity is retained, itmay be difficult to attain adequate fracture strength as a spacerparticle when a crosslinking density is low.

In dispersion polymerization, generally, a medium used in polymerizationis appropriately determined depending on a polymerizable monomer to beused, but as an organic solvent which is generally suitable, there canbe given, for example, alcohols, cellosolves, ketones or hydrocarbon,and further these solvents alone or mixed solvents of these solvents,and another compatible organic solvent or water are given. As an organicsolvent used for the mixed solvent, there are given, for example,acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, ethyl acetate,alcohols such as methanol, ethanol, propanol; cellosolves such as methylcellosolve, ethyl cellosolve, and the like; and ketones such as acetone,methyl ethyl ketone, methyl butyl ketone, 2-butanone.

The above-mentioned spacer particle preferably has compressive modulusof elasticity (10% K value) of 2000 to 15000 MPa at 10% deformation.When the compressive modulus of elasticity is less than 2000 MPa, thespacer particle may be deformed by press pressure in assembling adisplay device and therefore a proper gap may not be maintained. When itis more than 15000 MPa, the spacer particle may damage an orientationlayer on the substrate to cause display anomalies in incorporating it ina display device. In addition, the above 10% K value can be determined,for example, by using Micro Compression Testing Machine (PCT-200manufactured by SHIMADZU CORPORATION) according to Japanese KouhyouPublication Hei-6-503180 and measuring the load which deforms the fineparticle by 10% with a flat end face of a diamond column of 50 μm indiameter.

The above spacer particle may be colored in order to improve contrast ofa display device. As a method for coloring the above spacer particle,there are given, for example, a method for containing carbon black,disperse dye, acid dye, basic dye and metal oxide; and a method in whichan organic film is formed on the surface of spacer particle and thisfilm is decomposed or carbonized at elevated temperatures. Further, whena material, composing a spacer particle, itself has a color, it may beused as is without coloring.

With respect to the above spacer particle, an adhesive layer may beprovided for the surface or surface modification for preventing theorientation of adjacent liquid crystal from being disturbed may beapplied to the surface. As a method for applying the above surfacemodification, there are given a method for modifying by depositing resinon the surface of the spacer particle as disclosed in Japanese KokaiPublication Hei-1-247154; a method for modifying by reacting a compoundwhich can react with a functional group on the surface of spacerparticle as disclosed in Japanese Kokai Publication Hei-9-113915; and amethod for graft-polymerizing at the surface of the spacer particle asdescribed in Japanese Kokai Publication Hei-11-223821. Among others, itis preferred to form a surface coating layer chemically combined withthe surface of a spacer particle because of the less occurrence ofproblems of peeling of the surface layer or elution of the surface layerinto liquid crystal in a cell of a liquid crystal display, and forexample, a method for graft-polymerizing at the surface by reacting areducing group on the surface of a spacer particle with an oxidizingagent to produce a free radical is preferred in that it is possible toform a surface layer having a high density and an sufficient thickness.

And, on the surface of a fine particle, there may be formed a surfacecoating layer formed by chemically combining securely a vinyl-basedthermoplastic resin, formed by polymerizing vinyl-based monomers, withthe surface of a fine particle through graft polymerization. Such asurface coating layer is preferred because of the less occurrence ofproblems such as peeling or elution of the surface coating layer in inkof ink-jet method or a cell of a liquid crystal display.

The vinyl-based monomer composing the above vinyl-based thermoplasticresin is not particularly limited and includes, for example, vinyl-basedmonomers having hydroxyl group such as 2-hydroxyethyl (meth)acrylate,1,4-hydroxybutyl (meth)acrylate, (poly)caprolactone-modifiedhydroxyethyl (meth)acrylate, allyl alcohol and glycerin mono allylether; acrylic acids and α-alkyl derivatives or β-alkyl derivativesthereof such as (meth)acrylic acid, α-ethyl acrylic acid and crotonicacid; unsaturated dicarboxylic acids such as fumaric acid, maleic acid,citraconic acid and itaconic acid; vinyl-based monomers havingcarboxylic groups such as derivatives of mono-2-(meth)acryloyloxyethylester of the above unsaturated dicarboxylic acids; vinyl-based monomershaving a sulfonyl group such as t-butylacrylamidesulfonic acid,styrenesulfonic acid and 2-acrylamido-2-methyl propane sulfonic acid;vinyl-based monomers having a phosphonyl group such as vinyl phosphateand 2-(meth)acryloyloxyethyl phosphate; vinyl-based monomers having anamino group like amines having acryloyl groups such asdimethylaminoethyl methacrylate and diethylaminoethyl methacrylate;vinyl-based monomers having ether groups such as terminal alkyl ether of(poly)ethylene glycol (meth)acrylate, terminal alkyl ether of(poly)propylene glycol (meth)acrylate and tetrahydrofurfuryl(meth)acrylate; vinyl-based monomers having an amide group such as(meth)acrylamide, methylol(meth)acrylamide and vinylpyrrolidone;(meth)acrylate esters such as methyl (meth)acrylate, ethyl(meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate,n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate,cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl(meth)acrylate, stearyle (meth)acrylate, isostearyle (meth)acrylate,isodecyl (meth)acrylate, tridecyl (meth)acrylate, isobornyl(meth)acrylate, phenyl (meth)acrylate, benzil (meth)acrylate,methyl-α-chloro (meth)acrylate and glycidyl (meth)acrylate; unsaturatednitriles such as acrylonitrile and methacrylonitrile; maleimides such asphenylmaleimide and cyclohexylmaleimide; vinyl esters such as vinylacetate and vinyl propionate; vinyl ethers such as ethyl vinyl ether andbutyl vinyl ether; vinyl halides such as vinyl chloride and vinylbromide; vinyl-based monomers, each of which has at least onepolymerizable unsaturated double bond in a molecule, such as olefinslike ethylene, propylene, 1-butene, 2-butene and butadiene, and styreneand derivatives thereof like styrene and α-methylstyrene. Thesevinyl-based monomers may be used alone or may be used in combination oftwo or more species.

The content of the above spacer particle in the above dispersion ofspacer particles is preferably 0.05 to 5% by weight. When the content isless than 0.05% by weight, the probability of not containing the spacerparticle in an ejected droplet increases. When it is more than 5% byweight, a nozzle of an ink-jet system may become apt to clog or numberof spacers contained in a droplet of the dispersion having adheredbecomes too many and therefore the spacer particle may become less proneto move during the course of drying. The content is more preferably 0.1to 2% by weight.

The above-mentioned spacer particles are preferably dispersed in theform of a single particle in the dispersion of spacer particles. Whencohesion particles are present in the dispersion of spacer particles,not only they cause the reduction in ejection accuracy, but also theymight cause clogging of a nozzle of an ink-jet system in an extremecase.

The above-mentioned medium of the dispersion of spacer particles is notparticularly limited as long as being liquid at room temperature andamong others, water-soluble or hydrophilic liquid is preferred.Generally, a head of an ink-jet system trends to be able to eject aliquid stably in the case of using hydrophilic liquid. When a highlyhydrophobic organic solvent is used as the medium, the medium may affecta member composing a head or may elute a part of adhesives, which bondthe member. The above-mentioned medium should not have an orientationlayer-contaminating property of penetrating into the orientation layerformed on a substrate or dissolving the orientation layer. Generally,the above orientation layer comprises polyimide resin and controls theorientation of liquid crystal by being subjected to rubbing of thesurface.

As the above-mentioned water-soluble or hydrophilic liquid, there aregiven, for example, in addition to water, monoalcohols such as ethanol,n-propanol, 2-propanol, 1-butanol, 2-butanol, 1-methoxy-2-propanol,furfuryl alcohol, tetrahydrofurfuryl alcohol, and the like; polymers ofethylene glycol such as ethylene glycol, diethylene glycol, triethyleneglycol, tetraethylene glycol, and the like; lower monoalkyl ethers suchas monomethyl ether, monoethyl ether, monoisopropyl ether, monopropylether and monobutyl ether of ethylene glycol and polymers of ethyleneglycol, respectively; lower dialkyl ethers such as dimethyl ether,diethyl ether, diisopropyl ether, dipropyl ether, and the like; alkylesters such as monoacetate, diacetate, and the like; polymers ofpropylene glycol such as propylene glycol, dipropylene glycol,tripropylene glycol, tetrapropylene glycol, and the like; lowermonoalkyl ethers such as monomethyl ether, monoethyl ether,monoisopropyl ether, monopropyl ether and monobutyl ether of propyleneglycol and polymers of propylene glycol, respectively; lower dialkylethers such as dimethyl ether, diethyl ether, diisopropyl ether,dipropyl ether, and the like; alkyl esters such as monoacetate,diacetate, and the like; diols such as 1,3-propanediol, 1,2-butanediol,1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol,3-hexene-2,5-diol, 1,5-pentanediol, 2,4-pentanediol,2-methyl-2,4-pentanediol, 2,5-hexanediol, 1,6-hexanediol, neopentylglycohol, and the like; ether derivatives of diols; acetate derivativesof diols; polyhydric alcohols or ether derivatives thereof such asglycerin, 1,2,4-butanetriol, 1,2,6-hexanetriol, 1,2,5-pentanetriol,trimethylol propane, trimethylol ethane, pentaerythritol, and the like;acetate derivatives; dimethyl sulfoxide, thiodiglycol,N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, γ-butyrolactone,1,3-dimethyl-2-imidazolidine, sulfolane, formamide,N,N-dimethylformamide, N,N-diethylformamide, N-methylformamide,acetamide, N-methylacetamide, α-terpineol, ethylene carbonate, propylenecarbonate, bis(β-hydroxyethyl)sulfone, bis(β-hydroxyethyl) urea,N,N-diethylethanolamine, abietynol, diacetone alcohol and urea.

Preferably, the above-mentioned medium of the dispersion of spacerparticles contains a liquid having a boiling point of less than 100° C.at an atmospheric pressure of 1 atm. Since such a liquid volatilizes atrelatively low temperature as the dispersion of spacer particles isevaporated after being ejected onto the substrate, a drying temperaturemay be set low. When the drying temperature is set low, it is possibleto inhibit the medium from contaminating an orientation layer inevaporating the medium to impair the picture quality of display of aliquid crystal display. More preferably, the medium contains an organicsolvent having a boiling point of 70° C. or more and less than 100° C.As such an organic solvent, there are given lower monoalcohols such asethanol, n-propanol, 2-propanol and the like, and acetone.

Preferably, the above-mentioned liquid having a boiling point of lessthan 100° C. has the surface tension of 25 mN/m or less at 20° C.Generally, an ink-jet system exhibits good ejection accuracy when thesurface tension of a liquid to be ejected is 25 to 50 mN/m. On the otherhand, when the surface tension of a droplet of the dispersion ejectedonto a substrate is high, it is easier to move the spacer particleduring the course of drying. When the surface tension of the liquidhaving a boiling point of less than 100° C. is 25 mN/m or less, at themoment when the dispersion is ejected, the surface tension of thedispersion of spacer particles can be set relatively low and thereforegood ejection accuracy is attained, and on the other hand after themoment when the dispersion adheres to the substrate, since the liquidvolatilizes faster than another components in the dispersion of spacerparticles, the surface tension of the dispersion becomes large andtherefore the spacer becomes apt to move.

The content of the above-mentioned liquid having a boiling point of lessthan 100° C. in the above dispersion of spacer particles is preferably10 to 80% by weight. When this content is less than 10% by weight, anevaporating rate of the dispersion becomes slow in a relatively lowdrying temperature applied in the method for manufacturing a liquidcrystal display according to the first aspect of the present inventionand therefore production efficiency may be reduced, and when it is morethan 80% by weight, the dispersion of spacer particles adjoining thenozzle of the ink-jet system becomes apt to evaporate and therefore anejecting property of the ink-jet may be impaired, and the dispersion ofspacer particles becomes apt to evaporate in preparing the dispersion ofspacer particles or in a tank and therefore the possibility of producingcohesion spacers increases.

Preferably, the above-mentioned medium of the dispersion of spacerparticles contains a liquid having a boiling point of 150° C. or more atan atmospheric pressure of 1 atm. Such a liquid prevents the dispersionof spacer particles from evaporating excessively in the neighborhood ofthe nozzle of the ink-jet system to reduce the ejection accuracy orinhibits the dispersion of spacer particles from evaporating inpreparing the dispersion of spacer particles or in a tank to producecohesion spacers. More preferably, the medium contains a liquid having aboiling point of 150° C. or more and 200° C. or less. As such a liquid,there are given ethers of lower alcohol such as ethylene glycol,ethylene glycol monomethyl ether, ethylene glycol dimethyl ether and thelike.

Preferably, the above-mentioned liquid having a boiling point of 150° C.or more has the surface tension of 30 mN/m or more at 20° C. When thesurface tension of the liquid having a boiling point of 150° C. or moreis 30 mN/m or more, after the moment when a droplet of the dispersion ofspacer particles adheres to the substrate, the liquid having a lowerboiling point volatilizes earlier and then the surface tension of thedispersion of spacer particles is kept high and therefore the spacerbecomes apt to move.

The content of the above-mentioned liquid having a boiling point of 150°C. or more in the above dispersion of spacer particles is preferably 10to 80% by weight. When this content is less than 10% by weight, thereduction in ejection accuracy or the production of cohesion spacers dueto the evaporation of the dispersion of spacer particles may become aptto occur, and when it is more than 80% by weight, it takes significantlymuch time to dry and therefore production efficiency is reduced and inaddition to this the degradation of the display picture quality of aliquid crystal display due to the contamination of an orientation layerbecomes apt to occur.

The above medium of the dispersion of spacer particles, in addition, maycontain, for example, adhesive component for the purpose of impartingadhesion, or may contain a variety of surfactants or viscosity modifiersfor the purpose of improving the dispersibility and the mobility of thespacer particle or controlling physical properties such as the surfacetension and the viscosity to improve the ejection accuracy. The abovemedium of the dispersion of spacer particles may also contain onespecies or two or more species of various additives such as a tackifier,a pH regulator, an antifoamer, an antioxidant, a heat stabilizer, alight stabilizer, an ultraviolet absorber and a coloring agent asrequired to the extent that achievement of the issues of the presentinvention is not inhibited.

Preferably, the above dispersion of spacer particles has a contact angleof 25 to 70° relative to an orientation layer on a substrate. When thisangle is less than 25°, the spacer particle may be prone to move after adroplet of the dispersion of spacer particles adheres to the substrate,and when it is more than 70°, it may become difficult to eject thedispersion of spacer particles accurately.

Next, a process of ejecting the above dispersion of spacer particlesonto a substrate in the method for manufacturing a liquid crystaldisplay according to the first aspect of the present invention will bedescribed.

As an ink-jet system used in the method for manufacturing a liquidcrystal display according to the first aspect of the present invention,there can be used a system employing a publicly known method such as apiezo ink-jet method in which liquid is ejected by vibrations of apiezoelectric element and a method thermal ink-jet method in whichliquid is ejected with the aid of the expansion of liquid by rapidheating. A diameter of a nozzle hole of the above-mentioned ink-jetsystem is preferably 20 to 100 μm. If the nozzle hole diameter is lessthan 20 μm, when the dispersion of spacer particles having a particlediameter of 2 to 10 μm is ejected, ejection accuracy is reduced due tothe too small difference between the nozzle hole diameter and theparticle diameter, and extremely, the ejection of the dispersion ofspacer particles may become impossible due to nozzle clogging. When itis more than 100 μm, the precision of locating spacers may become roughsince the ejected liquid droplet becomes large and therefore thediameter of a droplet having adhered also becomes large.

A droplet diameter of the dispersion of spacer particles ejected fromthe nozzle of the above-mentioned ink-jet system is preferably 10 to 80μm. As a method for controlling the droplet diameter, there is given,for example, a method for optimizing the diameter of a nozzle hole or amethod for optimizing electrical signals controlling the ink-jet system.The latter is especially important in the case where an ink-jet systemof a piezo ink-jet method is employed. And, a diameter of an adheredliquid droplet to the substrate is preferably 30 to 150 μm. When thediameter is less than 30 μm, the diameter of a nozzle hole must be verysmall, and therefore a problem arises in terms of nozzle clogging withspacer particles and machining accuracy of a nozzle. When it is morethan 150 μm, the precision of locating spacers may become rough.

A substrate used in the method for manufacturing a liquid crystaldisplay according to the first aspect of the present invention is notparticularly limited and for example, a substrate, used as panelsubstrates of usual liquid crystal displays, such as a glass plate and aplastic plate can be used.

In the method for manufacturing liquid crystal displays according to thefirst aspect of the present invention, the spacer particles arepreferably located on the surface of one substrate of two substratesconstituting a liquid crystal display. And, the spacer particles on thesubstrate may be located on a random basis or may be located atspecified positions in specific patterns. The above spacer particles arepreferably located in a non-display area of the substrate in order toinhibit the reduction in display picture quality resulting from thespacer particle such as light leakage. It is thought that in the abovenon-display area, a shading layer referred to as a black matrix formedaround the pixel and a position of a TFT device in a TFT liquid crystaldisplay are located, but it is preferred to locate the spacer particlesin the black matrix portion so as not to break the TFT device.Generally, the number of spacer particles to be located is preferably 50to 300 per an area of 1 mm square. As far as the spacer particlesatisfies the condition of this particle density, it may be located inany part under the black matrix and in any pattern.

Next, there will be described a process of evaporating the medium in theabove dispersion of spacer particles after the dispersion of spacerparticles has adhered to the substrate in the method for manufacturing aliquid crystal display according to the first aspect of the presentinvention. In the method for manufacturing a liquid crystal displayaccording to the first aspect of the present invention, the medium indispersion of spacer particles is evaporated in such a way that adiameter D₁ of an adhered droplet of the dispersion of spacer particlesimmediately after the dispersion of spacer particles ejected from thenozzle of the ink-jet system has adhered to the substrate and a diameterD₂ of the adhering spacer particles, remaining after the dispersion ofspacer particles is evaporated, satisfy a relationship of Equation (1).D ₂<(D ₁×0.5)  (1)

In order to gather the spacer particles in the vicinity of a centralportion of the adhered droplet in an evaporating process of thedispersion of the spacer particles as described above, it becomesimportant to set the boiling point and the surface tension of the mediumin the dispersion of spacer particles, the contact angle of thedispersion of spacer particles relative to the orientation layer and theconcentration of the spacer particle in the dispersion of spacerparticles at favorable conditions as described above and also to set adrying temperature and a drying time at favorable conditions. Thecondition of evaporating the medium rapidly is not preferred in such away that the medium does not disappear during the spacer particles moveon the substrate in the course of drying. On the contrary, when thedrying time becomes significantly long, production efficiency of theliquid crystal display is lowered. And, if the medium contacts anorientation layer at elevated temperatures for a long time, this maycause the contamination of an orientation layer to impair the picturequality of display as a liquid crystal display. When the medium becomeapt to volatilize at room temperature, the dispersion of spacerparticles adjoining the nozzle of the ink-jet system becomes apt toevaporate, and therefore an ejecting property of the ink-jet may beimpaired and cohesion spacers may be produced in preparing thedispersion of spacer particles or due to evaporation in a tank.

Considering these limiting conditions, as preferred conditions ofdrying, there is given, for example, that the surface temperature of asubstrate at the time when the dispersion of spacer particles adheres tothe substrate is at least 20° C. lower than a boiling point of a liquidhaving the lowest boiling point among liquids contained in thedispersion. When the surface temperature of a substrate exceeds atemperature lower than a boiling point of a liquid having the lowestboiling point by 20° C., not only the liquid having the lowest boilingpoint is rapidly volatilized and therefore the spacer particles cannotmove, but also in an extreme case, the whole liquid droplet moves aroundon the substrate due to a rapid boil of the liquid and therefore theprecision of locating spacers may significantly deteriorates.

And, it is preferred that the surface temperature of a substrate is 90°C. or less during a time period until the dispersion of spacer particlesis completely evaporated. When the surface temperature exceeds 90° C.,this may cause the contamination of an orientation layer and picturequality of display of a liquid crystal display may be impaired. Morepreferably, the surface temperature is 70° C. or less. Incidentally, inthe present invention, a time when the liquid is completely evaporatedrefers to a time when a droplet on a substrate disappears.

The substrate, on which the spacer particles are located by such amethod, can be used for manufacturing a liquid crystal display by usingan opposed substrate and a peripheral sealing material and pressingagainst to each other under heating, and filling liquid crystal into thegap formed between these substrates.

In accordance with the method for manufacturing a liquid crystal displayaccording to the first aspect of the present invention, since it becomespossible to gather and locate the spacer particles in a smaller areathan a liquid droplet diameter having adhered in a process ofevaporating the dispersion of spacer particles, it is possible to locatethe spacer particles selectively also in a non-display area having anextremely narrow breadth. Thus, in a liquid crystal display manufacturedby the method for manufacturing a liquid crystal display according tothe first aspect of the present invention, there is not the reduction indisplay picture quality such as the occurrence of light leakage from acircumference of the spacer.

The second aspect of the present invention pertains to a substrate for aliquid crystal display, on which a color filter comprising a pixel areaarrayed in accordance with a given pattern and a shading area definingthe above pixel area is formed, and in which an orientation layer, acontact angle of which relative to the dispersion of spacer particles isθb, is present in an area representing the above pixel area and an area,a contact angle of which relative to the dispersion of spacer particlesis θa, is present at least in a part of an area representing the aboveshading area, and the above θa and the above θb satisfy a relationshipexpressed by Equation (2).θa<θb  (2)

In this specification, an area representing a pixel area refers to anarea lies immediately below the pixel area of a color filter when in astate of being assembled into a liquid crystal display, a display screenis horizontally placed with a substrate surface provided with a colorfilter up, and an area representing a shading area refers to an arealies immediately below the shading area of a color filter. In thisspecification, a contact angle refers to a static contact angle at atime when after a droplet of an objective liquid (dispersion of spacerparticles) is put on a plane, the droplet ceases to spread.

When the substrate for a liquid crystal display according to the secondaspect of the present invention is used, it is possible to spread theejected dispersion of spacer particles over the shading area with theshading area selectively wetted with the dispersion of spacer particles,and therefore it is possible to locate the spacer particles selectivelyin the shading area. When θb and θa do not satisfy a relationship ofEquation (2), it becomes impossible to locate the spacer particleselectively in the shading area.

The above area having a contact angle of θa may be continuously formedin a line in an area representing the shading area or may be formed inthe form of discontinuous islands having any shape. And, the area havinga contact angle of θa is preferably formed in bounds which is smallerthan the area representing the shading area and spaced inside themargins of the area representing the shading area. When the area havinga contact angle of θa is formed in contact with the margins of the arearepresenting the shading area, an area, in which orientation of liquidcrystal is not controlled, overruns out of the area representing theshading area and a area, in which orientation of liquid crystal is notcontrolled, is generated in an area representing the pixel area, andtherefore this may lead to a defect of the display quality of a liquidcrystal display.

The substrate for a liquid crystal display according to the secondaspect of the present invention is not particularly limited and asubstrate, used as panel substrates of usual liquid crystal displays,such as a glass plate and a plastic plate can be employed. And, a resinthin film for regulating an orientation of the liquid crystal, referredto as an orientation layer, is generally formed on the surface of thesubstrate for a liquid crystal display according to the second aspect ofthe present invention. Generally, the above orientation layer comprisespolyimide resin and controls the orientation of liquid crystal by beingsubjected to rubbing of the surface.

A method for manufacturing the substrate for a liquid crystal displayaccording to the second aspect of the present invention is notparticularly limited and includes, for example, a method in which afteran orientation layer is once formed, only the orientation layer in theposition, at which the spacer particle is chosen to be locate, isprocessed afterward by way of removal, modification or coating; and amethod for forming an orientation layer only in the position at whichthe spacer particle is chosen not to be locate. These method may be usedalone, respectively, or may be used in combination of both species.

As the above-mentioned method in which after an orientation layer isonce formed, only the orientation layer in the position, at which thespacer particle is chosen to be locate, is processed afterward by way ofremoval, modification or coating, there is given, for example, a methodin which after an orientation layer, a contact angle of which relativeto the dispersion of spacer particles is θb, is uniformly formed on thewhole surface of a substrate, by applying non-contact energy irradiationto a position at which the spacer particle is chosen to be located, theorientation layer in the position is removed or modified to bring acontact angle relative to the dispersion of spacer particles into θa.Such a method for manufacturing the substrate for a liquid crystaldisplay according to the second aspect of the present invention alsoconstitutes the present invention.

In the method for manufacturing the substrate for a liquid crystaldisplay of the present invention, it is preferred that an orientationlayer is first formed, and by applying rubbing treatment to the surfaceof this orientation layer, the orientation of liquid crystal iscontrolled, and then non-contact energy is irradiated to a position atwhich the spacer particle is chosen to be located.

A method for the above-mentioned irradiation of non-contact energy isnot particularly limited as long as it can converge a beam diameter ofthe energy irradiation so as to be 20 μm or less and cause anorientation layer material such as polyimide resin to decompose,vaporize, burn and oxidize and any method can be employed, but forexample, laser irradiation, excimer laser irradiation, corona dischargetreatment and low temperature plasma treatment are given. In accordancewith these method for the irradiation of non-contact energy, since theorientation layer can be removed or modified without contacting thesurface of the orientation layer after the orientation of liquid crystalis controlled by previously applying rubbing treatment to the surface ofthe orientation layer, an orientation layer, in which orientation ofliquid crystal is controlled, cam be relatively easily obtained. Thesemethod for the irradiation of non-contact energy may be used alone ormay be used in combination of two or more species.

And, the method for coating only the position, at which the spacerparticle is chosen to be locate, with the orientation layer is notparticularly limited but includes, among others, a method for forming aheterogeneous film on the surface of the orientation layer by treatmenttechniques such as vapor deposition through the medium of a mask,sputtering, CVD (Chemical Vapor Deposition) and plasma polymerization.These treatment techniques may be used alone or may be used incombination of two or more species.

As the method for forming an orientation layer only in the position atwhich the spacer particle is chosen not to be locate, there is given,for example, a method, in which a photosensitive polyimide resinprecursor or a photosensitive polyimide resin is uniformly applied to asubstrate having a surface, a contact angle of which relative to thedispersion of spacer particles is θa, and by exposing the photosensitivepolyimide film through the medium of a mask and developing the film, anorientation layer comprising polyimide resin is formed in the form of apattern on the surface of the substrate other than the position at whichthe spacer particle is chosen to be locate and a contact angle of thesurface of the above orientation layer relative to the dispersion ofspacer particles is brought into θb.

Such a method for manufacturing the substrate for a liquid crystaldisplay according to the second aspect of the present invention alsoconstitutes the present invention.

Though this method for manufacturing the substrate for a liquid crystaldisplay of the present invention needs to apply rubbing treatment to thewhole surface of a substrate after an orientation layer in the form of apattern is once formed on the substrate, it has an advantage that eventhough rubbing treatment is applied after the orientation layercomprising polyimide resin is coated with a high polar film, a problemof peeling of the high polar film does not arise. And, an orientationlayer comprising polyimide resin may be formed by depositing a polyimideresin precursor only on an area requiring an orientation layer on thesubstrate through the medium of a mask provided with a pattern havingopenings corresponding to areas intended for the formation of theorientation layer by treatment techniques such as vapor deposition,sputtering, CVD and plasma polymerization.

A method for manufacturing a liquid crystal display using the substratefor a liquid crystal display according to the second aspect of thepresent invention, in which the dispersion of spacer particles isejected onto the area where a contact angle of the substrate for aliquid crystal display relative to the dispersion of spacer particles isθa to locate the spacer particle, also constitutes the presentinvention.

The spacer particle and the dispersion of spacer particles, a method forejecting the dispersion of spacer particles and a method for evaporatinga liquid droplet having adhered to a substrate, used in the secondaspect of the present invention, is not particularly limited and aconventional substance of method publicly known may be used, but asubstance of method used in the method for manufacturing a liquidcrystal display according to the first aspect of the present inventionis preferably used.

After the spacer particles are located selectively on the substrate fora liquid crystal display according to the second aspect of the presentinvention by such a method, this substrate and an opposed substrate arepressed against to each other under heating through the medium of aperipheral sealing material, and liquid crystal is filled into the gapformed between these substrates, and therefore a desired liquid crystaldisplay can be obtained.

The substrate for a liquid crystal display according to the secondaspect of the present invention can be applied to either a STN typeliquid crystal display or a TFT type liquid crystal display.

The above-mentioned STN type liquid crystal display comprises a colorfilter substrate provided with a color filter and an opposed substratelocated on opposite side to the color filter substrate, and the aboveboth substrates have transparent electrodes formed in the form ofstripe, and the substrate for a liquid crystal display according to thesecond aspect of the present invention may be used for any substratedescribed above.

The above-mentioned TFT type liquid crystal display comprises a colorfilter substrate provided with a color filter and an opposed substratelocated on opposite side to the color filter substrate, and the opposedsubstrate generally has an array such as TFT device and referred to asan array substrate. Generally, a contact transparent electrode is formedon the color filter substrate, and a device and the transparentelectrode are formed on the array substrate, and the substrate for aliquid crystal display according to the second aspect of the presentinvention may be used for any substrate described above.

If the substrate for a liquid crystal display according to the secondaspect of the present invention is used, since the dispersion of spacerparticles is ejected onto the area where a contact angle relative to thedispersion of spacer particles is θa with an ink-jet system, it ispossible to locate the spacer particles selectively in a non-displayarea of the substrate with efficiency and high accuracy and to attain aliquid crystal display which exhibits excellent display quality withoutthe occurrence of a depolarization phenomenon resulting from the spacerparticle and the reduction in contrast and color tone due to lightleakage.

The third aspect of the present invention pertains to a dispersion ofspacer particles, which comprises spacer particles in which avinyl-based thermoplastic resin, formed by free radical polymerizingvinyl-based monomers having a hydrophilic functional group and/or analkyl group having 3 to 22 carbon atoms, is combine with the surface ofan inorganic fine particle and/or an organic fine particle by graftpolymerization and a medium composed of water and/or a hydrophilicorganic solvent and having the surface tension of 25 to 50 mN/m at 20°C., and in which the spacer particles are dispersed in the form of asingle particle in the medium.

The above-mentioned inorganic fine particle used for the dispersion ofspacer particles according to the third aspect of the present inventionis not particularly limited but include, among others, a silica fineparticle and the like. These inorganic fine particles may be used aloneor may be used in combination of two or more species. Also, theabove-mentioned organic fine particle is not particularly limited butinclude, among others, a resin fine particle and the like. These organicfine particles may be used alone or may be used in combination of two ormore species. Further, the above inorganic fine particle and organicfine particle may be used alone, respectively, or may be used incombination of both species. Among others, a resin fine particle isfavorably used since it has the advantages that it has adequate hardnessnot to damage the orientation layer formed on the substrate of theliquid crystal display and is easy to follow the change in thickness dueto thermal expansion or thermal contraction, and further is relativelyless in the move of a spacer within a cell.

As resin composing the above resin fine particle, there can be employed,for example, a resin similar to that used for the spacer particle usedin the method for manufacturing a liquid crystal display according tothe first aspect of the present invention, and the resin fine particlecan be obtained in the same method.

In the spacer particles used for the dispersion of spacer particlesaccording to the third aspect of the present invention, a vinyl-basedthermoplastic resin, formed by free radical polymerizing vinyl-basedmonomers having a hydrophilic functional group and/or an alkyl grouphaving 3 to 22 carbon atoms, is combine with the surface of theabove-mentioned inorganic fine particle or organic fine particle bygraft polymerization.

The above-mentioned hydrophilic functional group is not particularlylimited but for example, it is preferably at least one species selectedfrom the group consisting of hydroxyl group, carboxyl group, sulfonylgroup, phosphonyl group, amino group, amide group, ether group, thiolgroup and thioether group. Among others, hydroxyl group, carboxyl groupand ether group are more preferred because of less interaction withliquid crystal. These hydrophilic functional groups may be used alone ormay be used in combination of two or more species.

The vinyl-based monomer having above hydrophilic functional group is notparticularly limited and includes, for example, vinyl-based monomershaving hydroxyl group such as 2-hydroxyethyl (meth)acrylate,1,4-hydroxybutyl (meth)acrylate, (poly)caprolactone-modifiedhydroxyethyl (meth)acrylate, allyl alcohol and glycerin mono allylether; acrylic acids and α-alkyl derivatives or β-alkyl derivativesthereof such as (meth)acrylic acid, α-ethyl acrylic acid and crotonicacid; unsaturated dicarboxylic acids such as fumaric acid, maleic acid,citraconic acid and itaconic acid; vinyl-based monomers havingcarboxylic groups such as derivatives of mono-2-(meth)acryloyloxyethylester of the above unsaturated dicarboxylic acids; vinyl-based monomershaving a sulfonyl group such as t-butylacrylamidesulfonic acid,styrenesulfonic acid and 2-acrylamido-2-methyl propane sulfonic acid;vinyl-based monomers having a phosphonyl group such as vinyl phosphateand 2-(meth)acryloyloxyethyl phosphate; vinyl-based monomers having anamino group such as dimethylaminoethyl methacrylate anddiethylaminoethyl methacrylate; vinyl-based monomers having ether groupssuch as terminal alkyl ether of (poly)ethylene glycol (meth)acrylate,terminal alkyl ether of (poly)propylene glycol (meth)acrylate andtetrahydrofurfuryl (meth)acrylate; vinyl-based monomers having hydroxylgroup and ether group such as (poly)ethylene glycol (meth)acrylate and(poly)propylene glycol (meth)acrylate; and vinyl-based monomers havingan amide group such as (meth)acrylamide, methylol(meth)acrylamide andvinylpyrrolidone. These vinyl-based monomers having the hydrophilicfunctional group may be used alone or may be used in combination of twoor more species.

The above-mentioned alkyl group having 3 to 22 carbon atoms is notparticularly limited and includes, for example, n-propyl group, i-propylgroup, n-butyl group, i-butyl group, t-butyl group, n-pentyl group,n-hexyl group, cyclohexyl group, 2-ethylhexyl group, n-heptyl group,n-octyl group, n-nonyl group, decyl group, undecyl group, dodecyl group,tridecyl group, tetradecyl group, pentadecyl group, nonadecyl group,eicodecyl group, henicocyl group, docosyl group and isobornyl group.These alkyl groups having 3 to 22 carbon atoms may be used alone or maybe used in combination of two or more species.

The vinyl-based monomers having above-mentioned alkyl group having 3 to22 carbon atoms is not particularly limited and for example, estercompounds consisting of (meth)acrylic acid and the above alkyl grouphaving 3 to 22 carbon atoms; ester compounds consisting of vinyl alcoholand the above alkyl group having 3 to 22 carbon atoms; and vinyl ethercompounds consisting of a vinyl group and the above alkyl group having 3to 22 carbon atoms are given. These vinyl-based monomers having an alkylgroup having 3 to 22 carbon atoms may be used alone or may be used incombination of two or more species.

The vinyl-based monomer having above hydrophilic functional group andthe above vinyl-based monomer having an alkyl group having 3 to 22carbon atoms may be used alone, respectively, or may be used incombination of both species. Particularly, it is preferred that thevinyl-based monomer, composing the vinyl-based thermoplastic resin,contains the vinyl-based monomer having the above hydrophilic functionalgroup in an amount of 30 to 80% by weight and the vinyl-based monomerhaving the above alkyl group having 3 to 22 carbon atoms in an amount of20 to 60% by weight. When the content of the vinyl-based monomer havingabove hydrophilic functional group in the vinyl-based monomer is lessthan 30% by weight, it becomes difficult to disperse the obtained spacerparticle sufficiently in the form of a single particle in a medium ofthe dispersion and cohesion spacers become apt to arise, so that stableejection in an ink-jet system or a formation of an accurate cell gap maybecomes difficult. When the is more than 80% by weight, abnormalorientation of liquid crystal may become apt to occur on the surface ofa spacer which has overrun into display pixels in forming a cell of aliquid crystal display, leading to the reduction in display quality.And, when the content of the vinyl-based monomer having the above alkylgroup having 3 to 22 carbon atoms in the vinyl-based monomer is lessthan 20% by weight, abnormal orientation of liquid crystal may becomeapt to occur on the surface of a spacer particle which has overrun intodisplay pixels in forming a cell of a liquid crystal display, leading tothe reduction in display quality. When it is more than 60% by weight,the stability of dispersion of the resulting spacer particle in a mediummay be reduced.

In addition, when a surface coating layer composed of a vinyl-basedthermoplastic resin is formed by combining the vinyl-based thermoplasticresin, formed by free radical polymerizing vinyl-based monomers havingthe above-mentioned hydrophilic functional group and/or alkyl grouphaving 3 to 22 carbon atoms, with the surface of a fine particle bygraft polymerization, in the case where a plurality of vinyl-basedthermoplastic resin layers having different compositions are laminatedfor the purpose of thickening the surface coating layer, use of apreferred vinyl-based monomer, containing the vinyl-based monomer havingthe above hydrophilic functional group in an amount of 30 to 80% byweight and the vinyl-based monomer having the above alkyl group having 3to 22 carbon atoms in an amount of 20 to 60% by weight, may beconsidered only for an outermost vinyl-based thermoplastic resin layerof the surface coating layer. The reason for this is that exerting thefunction, such as the dispersibility in the medium used for dispersionof spacers or ink of ink-jet method and the inhibition of abnormalorientation of liquid crystal, depends on a state of and around thespacer surface.

In the spacer particle used for the dispersion of spacer particlesaccording to the third aspect of the present invention, the surfacecoating layer consisting of a vinyl-based thermoplastic resin is formedon the surface of a fine particle by chemically combining securely theabove-mentioned vinyl-based thermoplastic resin with the above thesurface of a fine particle through graft polymerization. The surfacecoating layer formed by such a method is preferred because of the lessoccurrence of problems such as peeling or elution of the surface coatinglayer in ink of ink-jet method or a cell of a liquid crystal display.Among others, for example as described in Japanese Kokai PublicationHei-11-223821, a method, in which a fine particle having a reducinggroup on its surface is reacted with an oxidizing agent to produce afree radical at the surface of a fine particle and by graftpolymerization originating from this free radical, a surface coatinglayer consisting of a vinyl-based thermoplastic resin is formed on thesurface of a fine particle, is preferred in that it is possible to forma surface coating layer having a high density and an sufficientthickness.

The content of the above spacer particle in the dispersion of spacerparticles according to the third aspect of the present invention ispreferably 0.05 to 5% by weight. When the content is less than 0.05% byweight, the probability of not containing the spacer particle in anejected droplet increases. When it is more than 5% by weight, a nozzleof an ink-jet system may become apt to clog or number of spacerscontained in a droplet of the dispersion having adhered becomes too manyand therefore the spacer particle may become less prone to move duringthe course of drying. The content is more preferably 0.1 to 2% byweight.

The above-mentioned spacer particles are dispersed in the form of asingle particle in the dispersion of spacer particles according to thethird aspect of the present invention. When cohesion particles arepresent in the dispersion of spacer particles, not only they cause thereduction in ejection accuracy, but also they might cause clogging of anozzle of an ink-jet system in an extreme case.

The medium constituting the dispersion of spacer particles according tothe third aspect of the present invention comprises water and/or ahydrophilic organic solvent. Generally, the ink-jet system trends to beable to eject a liquid stably in the case where the medium is water or ahydrophilic organic solvent, and in the case where the medium is ahighly hydrophobic organic solvent, there is a problem that a membercomposing a head is affected by the medium or a part of adhesives, whichbond the member, is eluted into the medium.

The above water is not particularly limited and for example,ion-exchanged water, pure water, groundwater, running water andindustrial water can be given. These water may be used alone or may beused in combination of two or more species.

The above-mentioned hydrophilic organic solvent is not particularlylimited and includes, for example, monoalcohols such as ethanol,n-propanol, 2-propanol, 1-butanol, 2-butanol, 1-methoxy-2-propanol,furfuryl alcohol, tetrahydrofurfuryl alcohol, and the like; polymers ofethylene glycol such as ethylene glycol, diethylene glycol, triethyleneglycol, tetraethylene glycol, and the like; polymers of propylene glycolsuch as propylene glycol, dipropylene glycol, tripropylene glycol,tetrapropylene glycol, and the like; lower monoalkyl ethers such asmonomethyl ether, monoethyl ether, monoisopropyl ether, monopropyl etherand monobutyl ether of polymers of ethylene glycol and polymers ofpropylene glycol; lower dialkyl ethers such as dimethyl ether, diethylether, diisopropyl ether and dipropyl ether of polymers of ethyleneglycol and polymers of propylene glycol; alkyl esters such asmonoacetate and diacetate of polymers of ethylene glycol and polymers ofpropylene glycol; diols such as 1,3-propanediol, 1,2-butanediol,1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol,3-hexene-2,5-diol, 1,5-pentanediol, 2,4-pentanediol,2-methyl-2,4-pentanediol, 2,5-hexanediol, 1,6-hexanediol, neopentylglycohol, and the like; ether derivatives of diols; acetate derivativesof diols; polyhydric alcohols such as glycerin, 1,2,4-butanetriol,1,2,6-hexanetriol, 1,2,5-pentanetriol, trimethylol propane, trimethylolethane, pentaerythritol, and the like; ether derivatives of polyhydricalcohols; acetate derivatives of polyhydric alcohols; dimethylsulfoxide, thiodiglycol, N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone,γ-butyrolactone, 1,3-dimethyl-2-imidazolidine, sulfolane, formamide,N,N-dimethylformamide, N,N-diethylformamide, N-methylformamide,acetamide, N-methylacetamide, α-terpineol, ethylene carbonate, propylenecarbonate, bis(β-hydroxyethyl)sulfone, bis(β-hydroxyethyl) urea,N,N-diethylethanolamine, abietynol, diacetone alcohol and urea. Thesehydrophilic organic solvents may be used alone or may be used incombination of two or more species. And the water and the hydrophilicorganic solvent may be used alone or may be used in combination of bothspecies.

The surface tension at 20° C. of the medium of the dispersion of spacerparticles according to the third aspect of the present invention is 25to 50 mN/m. When the surface tension goes out of this range, an ejectingproperty and an ejection accuracy of the dispersion of spacer particlesaccording to the third aspect of the present invention in an ink-jetsystem become inadequate.

Preferably, the medium of the dispersion of spacer particles accordingto the third aspect of the present invention contains a liquid having aboiling point of less than 100° C. at an atmospheric pressure of 1 atm.Since such a liquid volatilizes at relatively low temperature as thedispersion of spacer particles is evaporated after being ejected ontothe substrate, a drying temperature may be set low. When the dryingtemperature is set low, it is possible to inhibit the medium fromcontaminating an orientation layer in evaporating the medium to impairthe picture quality of display of a liquid crystal display. Morepreferably, the medium contains an organic solvent having a boilingpoint of 70° C. or more and less than 100° C. As such an organicsolvent, there are given lower alcohols such as ethanol, n-propanol,2-propanol and the like, and acetone.

Preferably, the above-mentioned liquid having a boiling point of lessthan 100° C. has the surface tension of 25 mN/m or less at 20° C.Generally, an ink-jet system exhibits good ejection accuracy when thesurface tension of a liquid to be ejected is 25 to 50 mN/m. On the otherhand, when the surface tension of a droplet of the dispersion ejectedonto a substrate is high, it is easier to move the spacer particleduring the course of drying. When the surface tension of the liquidhaving a boiling point of less than 100° C. is 25 mN/m or less, at themoment when the dispersion is ejected, the surface tension of thedispersion of spacer particles can be set relatively low and thereforegood ejection accuracy is attained, and on the other hand after themoment when the dispersion adheres to the substrate, since the liquidvolatilizes faster than another components in the dispersion of spacerparticles, the surface tension of the dispersion becomes large andtherefore the spacer becomes apt to move.

The content of the above-mentioned liquid having a boiling point of lessthan 100° C. in the medium of the dispersion of spacer particlesaccording to the third aspect of the present invention is preferably 10to 80% by weight. When this content is less than 10% by weight, anevaporating rate of the dispersion becomes slow in a relatively lowdrying temperature and therefore production efficiency may be reduced,and when it is more than 80% by weight, the dispersion of spacerparticles adjoining the nozzle of the ink-jet system becomes apt toevaporate and therefore an ejecting property of the ink-jet may beimpaired, and the dispersion of spacer particles becomes apt toevaporate in preparing the dispersion of spacer particles or in a tankand therefore the possibility of producing cohesion spacers increases.

Preferably, the medium of the dispersion of spacer particles accordingto the third aspect of the present invention contains a liquid having aboiling point of 150° C. or more at an atmospheric pressure of 1 atm.Such a liquid prevents the dispersion of spacer particles fromevaporating excessively in the neighborhood of the nozzle of the ink-jetsystem to reduce the ejection accuracy or inhibits the dispersion ofspacer particles from evaporating in preparing the dispersion of spacerparticles or in a tank to produce cohesion spacers. More preferably, themedium contains a liquid having a boiling point of 150° C. or more and200° C. or less. As such a liquid, there are given ethers of loweralcohol such as ethylene glycol, ethylene glycol monomethyl ether,ethylene glycol dimethyl ether and the like.

Preferably, the above-mentioned liquid having a boiling point of 150° C.or more has the surface tension of 30 mN/m or more at 20° C. When thesurface tension of the liquid having a boiling point of 150° C. or moreis 30 mN/m or more, after the moment when a droplet of the dispersion ofspacer particles adheres to the substrate, the liquid having a lowerboiling point volatilizes earlier and then the surface tension of thedispersion of spacer particles is kept high and therefore the spacerbecomes apt to move.

The content of the above-mentioned liquid having a boiling point of 150°C. or more in the dispersion of spacer particles according to the thirdaspect of the present invention is preferably 10 to 80% by weight. Whenthis content is less than 10% by weight, the reduction in ejectionaccuracy or the production of cohesion spacers due to the evaporation ofthe dispersion of spacer particles may become apt to occur, and when itis more than 80% by weight, it takes significantly much time to dry andtherefore production efficiency is reduced and in addition to this thedegradation of the display picture quality of a liquid crystal displaydue to the contamination of an orientation layer becomes apt to occur.

The dispersion of spacer particles according to the third aspect of thepresent invention may contain one species or two or more species ofvarious additives such as a tackifier, a viscosity regulator, a pHregulator, a surfactant, an antifoamer, an antioxidant, a heatstabilizer, a light stabilizer, an ultraviolet absorber and a coloringagent as required to the extent that achievement of the issues of thepresent invention is not inhibited.

The dispersion of spacer particles according to the third aspect of thepresent invention can be suitably used to be located at an arbitraryposition on a substrate for a liquid crystal display by an ink-jetmethod. An ink-jet system, which can be employed, is not particularlylimited and the above-mentioned system can be employed.

When the dispersion of spacer particles according to the third aspect ofthe present invention is used, an extremely excellent ejecting propertyis exhibited in ejecting the dispersion of spacer particles onto asubstrate for a liquid crystal display with an ink-jet system and a cellgap can be maintained accurately after drying, and therefore a liquidcrystal display, which develops homogeneous display quality, can beattained. Further, there can be attained a liquid crystal display whichhardly causes abnormal orientation of liquid crystal on the surface ofspacer and develops excellent display quality even when a spacerparticle overruns into pixels in a cell of a liquid crystal display.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail byway of examples, but the present invention is not limited to theseexamples.

EXAMPLE 1

(1) Preparation of Spacer Particles

In a separable flask, 15 parts by weight of divinylbenzene, 5 parts byweight of isooctyl acrylate and 1.3 parts by weight of benzoyl peroxideas an initiator were put and mixed uniformly. Next, to this mixture, 20parts by weight of a 3% aqueous solution of polyvinyl alcohol (“GL-03”made by KURARAY CO., LTD.) and 0.5 parts by weight of sodium dodecylsulfate were charged and stirred well, and then 140 parts by weight ofion-exchanged water was added. The resulting solution was reacted at 80°C. for 15 hours under nitrogen flow while being stirred. The resultingfine particles were washed with hot water and acetone, and thenclassified and the acetone was volatilized to obtain spacer particles.An average particle diameter of the obtained fine particles was 5 μm anda CV value was 3.0%.

(2) Surface Treatment of Spacer Particles

5 parts by weight of the obtained fine particles was charged to amixture of 20 parts by weight of dimethyl sulfoxide (DMSO) and 20 partsby weight of hydroxyethyl methacrylate and dispersed with a sonicater,and then the mixture was stirred uniformly. Then, a nitrogen gas wasintroduced into a reaction system and the mixture was stirred at 30° C.for two hours. To this was added 10 parts by weight of a 0.1 mol/litersolution of diammonium cerium nitrate ([Ce(NH₄)₂](NO₃)₆) regulated by a1N aqueous solution of nitric acid and a reaction was continued for 5hours.

After the completion of polymerization reaction, a reactant was takenout and separated into particles and a reaction solution throughfiltration using a 3 μm membrane filter. These particles were adequatelywashed with ethanol and acetone and then dried under reduced pressurewith a vacuum drier to obtain spacer particles surface treated.

(3) Preparation of Dispersion of Spacer Particles

The obtained spacer particles surface treated was taken by an amountrequired so as to obtain a given concentration and gradually added tothe disperse medium having composition shown in Table 1 and dispersed bybeing adequately stirred while using a sonicater to prepare a dispersionof spacer particles 1. The resulting dispersion of spacer particles 1was filtered with a stainless screen with mesh size of 10 μm to removecohesion spacers and subjected to evaluation test in an ink-jet system.

(4) Location of Spacer Particles on Substrate

The above-mentioned dispersion of spacer particles was ejected onto asubstrate of initial temperature shown in Table 2 using an ink-jetsystem of a piezo ink-jet method, on which a head having a nozzle holediameter of 30 μm is mounted.

As a substrate, there was used a substance provided with an orientationlayer formed by applying uniformly a polyimide intermediate (“LP-64”made by Toray Industries, Inc.) to a color filter glass substrate, onthe surface of which a ITO transparent electrode was provided, usingspin coater, drying at 150° C. and then baking at 280° C. for 90 minutesto cure.

Since a black matrix of 20 μm in width is formed between pixels of acolor filter on a color filter substrate, it was selected to locatespacer particles at 150 μm spacing on this black matrix with an ink-jetsystem. And, the spacer particle was adjusted and located in such a waythat a distribution density of the spacer particle is 100 particles/mm².

When the spacer particles were ejected, a stage was heated by a heaterattached to the stage.

In order to dry the dispersion of spacer particles ejected onto asubstrate on the stage, the substrate, to which ejection of spacerparticles was completed, was immediately shifted to on a hot plateheated to predetermined temperature shown in Table 2 and dried. When atemperature of the substrate at the beginning of the ejection and atemperature of a hot plate for drying were different, the surfacetemperature of the substrate was gradually elevated.

After visually recognizing that the medium was completely dried, thesubstrate was allowed to stand at the as-is temperature for 30 minutes.

A color filter substrate in which the spacers were thus located and anopposed substrate were bonded to each other using a peripheral sealingmaterial, and an empty cell with a cell gap of 5 μm was produced bycuring the sealing material through heating at 150° C. for 1 hour, andafter filling liquid crystal into the cell by a vacuum method, a fillingport was sealed with an end-sealing material to obtain a liquid crystaldisplay cell.

(5) Evaluation

Surface tension at 20° C. and dispersibility of the dispersion of spacerparticles, a diameter D₁ of an adhered droplet when the dispersion ofspacer particles is ejected onto the substrate and a diameter D₂ of theadhering spacer particles after evaporation, a property of locatingspacer particle, display quality as a liquid crystal display, and purityof liquid crystal were evaluated based on the following measures.

The results of evaluation were shown in Table 2.

(Evaluation of Dispersibility of Dispersion of Spacer Particles)

The clogging in filtering the dispersion of spacer particles with astainless screen having a mesh size of 10 μm and the re-dispersion ofthe precipitated spacer particles were visually observed and thedispersibility was evaluated according to the following criteria.

⊚: There was little clogging on the stainless screen and the dispersionof spacer particles passed through it smoothly. And the re-dispersion ofthe spacer particles was good.

◯: The dispersion of spacer particles passed through the stainlessscreen, but some clogging was found on the stainless screen afterfiltration. The re-dispersion of the spacer particles was good.

Δ: There was much clogging on the stainless screen and the dispersion ofspacer particles did not pass through the screen smoothly, but thedispersion of spacer particles could be filtered at much expense intime. The spacers having precipitated with time were not dispersed againeven by shaking the container.

X: Clogging on the stainless screen was serious and the dispersion ofspacer particles did not pass through the screen at all. The spacershaving precipitated with time were not dispersed again even by shakingthe container.

(Evaluation of Property of Locating Spacer Particles)

The dispersion of spacer particles was filtered with a stainless screen(mesh size of 10 μm) to remove cohesion spacers and then ejected onto asubstrate using an ink-jet system of a piezo ink-jet method, on which ahead having a nozzle hole diameter of 30 μm is mounted.

As the above substrate, there was used a substance provided with anorientation layer formed by applying uniformly a polyimide intermediate(“LP-64” made by Toray Industries, Inc.) to a color filter glasssubstrate, on the surface of which a ITO transparent electrode wasprovided, using spin coater, drying at 150° C. and then baking at 280°C. for 90 minutes to cure. Since a black matrix of 20 μm in width isformed between pixels of a color filter on the above color filtersubstrate, it was selected to locate spacer at 150 μm spacing on thisblack matrix with an ink-jet system. And, the spacer was adjusted andlocated in such a way that a distribution density of the spacers is 100particles/mm². During the ejection of the above spacer, a substrate ofroom temperature was placed on a stage and the substrate, to whichejection of spacers was completed, was immediately shifted to on a hotplate heated to 90° C. and dried. After visually recognizing that themedium was completely dried, the substrate was allowed to stand at theas-is temperature for 30 minutes. After the spacer particles werelocated on the substrate by the above-mentioned method, a status of thespacer particles located was observed by a microscope and a property oflocating spacer particle was evaluated according to the followingcriteria.

⊚: Each line which the spacer particles are located has an equaldistance between lines and is straight, and no light leakage was found.

◯: Each line which the spacer particles are located has an equaldistance between lines and is straight, but a little light leakage wasfound.

Δ: Each line which the spacer particles are located has a differentdistance between lines and much light leakage was found.

X: Since the spacer particles were little ejected onto the substrate,they were not located and much light leakage was found.

(Evaluation of Display Quality of Liquid Crystal Display (1))

◯: In a display area, no spacer particles were found and nocontamination of an orientation layer was found.

Δ: In a display area, a few spacer particles were found butcontamination of an orientation layer was not found.

Δ^(X): In a display area, a few spacer particles were found and a littlelight leakage like a stain probably resulting from contamination of anorientation layer was found.

X: In a display area, many spacer particles were found but light leakagelike a stain probably resulting from contamination of an orientationlayer was found.

XX: In a display area, many spacer particles were found and large lightleakage like a stain probably resulting from contamination of anorientation layer was found.

(Evaluation of Display Quality of Liquid Crystal Display (2))

⊚: Overrunning of a spacer particle into a display area was not found.

◯: A spacer particle overrun into a display area very slightly.

Δ: Overrunning of a spacer particle into a display area was found.

X: Overrunning of a spacer particle into a display area and lightleakage resulting from the overrunning was found.

(Evaluation of Purity of Liquid Crystal)

0.1 g of spacer particles was dispersed in 2 ml of liquid crystal (tradename “ZLI-4720-000”, made by Merck Ltd.) and a dispersion was allowed tostand at 80° C. for 200 hours, and then liquid crystal was recovered andpurity of the liquid crystal was measured by gas chromatography.

EXAMPLES 2 TO 6, COMPARATIVE EXAMPLES 1 TO 6

Each test was conducted following the same manner as in Example 1 exceptfor preparing dispersions of spacer particles having the compositions ofTable 1 using the spacer particles surface treated prepared in Example 1and locating the spacer particles on the substrates under conditionsshown in Table 2 using the prepared dispersions of spacer particles andevaluating.

By the way, as for the dispersion of spacer particles 5, the medium hadhigh volatility, cohesion spacers were produced on the wall of acontainer for dispersion treatment and clogging occurred in filtrationby a stainless screen. TABLE 1 Dispersion of spacer particles 1 2 3 4 5Composition Isopropyl alcohol 20 20 30 — 90 (% by weight) Ethyleneglycol 60 60 — 70 — Water 20 20 70 30 10 Spacer particles 0.5 6.0 0.50.5 0.5

TABLE 2 Sub- strate Di- temper- Di- ameter Initial ature Dry- ameter D₂of Dis- Sub- Hot at ing- D₁ of adher- Property persion strate platecompletion com- an ing of Purity of Surface temper- temper- of pletionadhered spacer locating Display Display of liquid spacer tension Dis-ature ature drying time droplet particles spacer quality quality crystalparticles (mN/m) persibility (° C.) (° C.) (° C.) (sec) (μm) (μm)particles (1) (2) (%) Example1 1 35 ⊚ 45 45 45 13 80 16 ⊚ ◯ ⊚ 100Example2 1 35 ⊚ 45 70 60 8 80 19 ⊚ ◯ ⊚ 100 Example3 1 35 ⊚ 20 20 20 170080 25 ⊚ Δ Δ 100 Example4 1 35 ⊚ 20 70 60 15 80 15 ⊚ ◯ ⊚ 100 Example5 464 ◯ 20 70 60 35 70 20 ⊚ Δ^(X) Δ 100 Example6 4 64 ◯ 20 90 80 20 70 23 ⊚Δ^(X) Δ 100 Comparative 1 35 ⊚ 100 100 100 0.5 80 110 Δ X X X 100Example1 Comparative 1 35 ⊚ 80 80 80 1 80 95 Δ X X 100 Example2Comparative 1 35 ⊚ 45 150 100 1 80 130 Δ X X X 100 Example3 Comparative2 35 ⊚ 20 70 60 13 100 70 Δ X X 100 Example4 Comparative 3 29 ◯ 20 70 6020 120 80 Δ X X 100 Example5 Comparative 5 29 ⊚ 20 70 60 1 — — X — — 100Example6

EXAMPLE 7

(1) Preparation of Spacer Particle

To a separable flask, 15 parts by weight of divinylbenzene, 5 parts byweight of isooctyl acrylate and 1.3 parts by weight of benzoyl peroxideas an initiator were charged and mixed uniformly. Next, to this mixture,20 parts by weight of a 3% by weight aqueous solution of polyvinylalcohol (trade mark “KURARAY Poval GL-03” made by KURARAY CO., LTD.) and0.5 parts by weight of sodium dodecyl sulfate were charged and stirreduniformly, and then 140 parts by weight of ion-exchanged water wasadded. Then, this mixed aqueous solution was polymerized at 80° C. for15 hours under nitrogen flow while being stirred to obtain fineparticles. The obtained fine particles were adequately washed with hotwater and acetone, and then classified and the acetone was volatilizedto obtain spacer particles. An average particle diameter of the obtainedspacer particles was 5 μm and a CV value was 3.0%.

(2) Surface Treatment of Spacer Particles

5 parts by weight of the obtained spacer particles was charged to amixed aqueous solution comprising of 20 parts by weight of ion-exchangedwater and 10 parts by weight of hydroxyethyl methacrylate and dispersedwith a sonicater, and then the mixture was stirred uniformly. Then, areaction system was replaced with a nitrogen gas and the mixture wasstirred at 30° C. for 2 hours. Then, to the reaction system was added 10parts by weight of a 0.1 mol/liter aqueous solution of diammonium ceriumnitrate ([Ce(NH₄)₂] (NO₃)₆) regulated by a 1N aqueous solution of nitricacid, and after a polymerization reaction was conducted for 5 hours, areactant was taken out and separated into particles and a reactionsolution through filtration using a 3 μm membrane filter. The obtainedparticles were adequately washed with ethanol and acetone and then driedunder reduced pressure with a vacuum drier to obtain spacer particles,on the surface of which a vinyl-based thermoplastic resin is formed bygraft polymerization.

(3) Preparation of Dispersion of Spacer Particles

The obtained spacer particles was taken by an amount required in such away that a particle concentration is 0.3% by weight and gradually addedto the medium comprising a mixture solution of 20 parts by weight ofisopropyl alcohol, 60 parts by weight of ethylene glycol and 20 parts byweight of ion-exchanged water and dispersed uniformly by beingadequately stirred with a sonicater, and then the resulting dispersionof spacer particles was filtered with a stainless screen with mesh sizeof 10 μm and cohesion spacers were removed to prepare a dispersion ofspacer particles.

(4) Preparation of Substrate

The following three kinds of substrates were prepared using a colorfilter substrate, in which a black matrix of 15 μm in width was formedbetween pixels of a color filter and an ITO transparent contactelectrode was formed on an overcoat provided on a color layer

1. Substrate A: An orientation layer comprising polyimide resin wasuniformly formed on the whole area of the above-mentioned ITOtransparent contact electrode of the color filter substrate. On thisorientation layer, laser processing was applied in the form of stripe of8 μm in width to the black matrix portion of the color filter as shownin FIG. 2, and a surficial orientation layer (polyimide resin) wasremoved to prepare a substrate A exposing the ITO as a substrate. Acontact angle θa of the exposed ITO surface of the substrate A obtainedrelative to the dispersion of spacer particles obtained in a paragraph(3) was 25°, and a contact angle θb of the surficial orientation layerrelative to the dispersion of spacer particles obtained in a paragraph(3) was 50°.

2. Substrate B: By applying a photosensitive polyimide resin precursorto the whole area of the above-mentioned ITO transparent contactelectrode of the color filter substrate, exposing the photosensitivepolyimide film through the medium of a mask and developing the film, asubstrate B, in which in the black matrix portion of the color filter,an orientation layer comprising polyimide resin was not formed and theITO as a substrate was exposed in the form of stripe of 8 μm in width,as shown in FIG. 2, was prepared. A contact angle θa of the exposed ITOsurface of the substrate B obtained relative to the dispersion of spacerparticles obtained in a paragraph (3) was 25°, and a contact angle θb ofthe surficial orientation layer (polyimide resin) relative to thedispersion of spacer particles obtained in a paragraph (3) was 45°.

3. Substrate C: By following the same procedure as in the paragraph 1except for not applying laser processing, a substrate C, in which anorientation layer comprising polyimide resin was formed on the wholearea of an ITO transparent contact electrode, was prepared. A contactangle θb of the surficial orientation layer (polyimide resin) of thesubstrate C obtained relative to the dispersion of spacer particlesobtained in a paragraph (3) was 50°.

(5) Locating Spacer Particles on Substrate

A dispersion of spacer particles of 35 pL was ejected at 120 μm spacingonto the ITO surface (contact angle θa relative to the dispersion ofspacer particles: 25°) in the form of stripe on the substrate A (colorfilter substrate), which was exposed by applying laser processing, usingan ink-jet system of a piezo ink-jet method, on which a head having anozzle hole diameter of 30 μm is mounted, and then it was dried, and thespacer particles were located to prepare a substrate A (color filtersubstrate) in which the spacer particles were located. In addition, thespacer particle was adjusted and located in such a way that adistribution density of the spacer particles is 150 particles/mm².During locating the spacer particles, a substrate of room temperaturewas placed on a stage and the dispersion of spacer particles wasejected, the substrate, to which ejection of spacer particles wascompleted, was immediately shifted to on a hot plate heated to 90° C.and dried. After visually recognizing that the medium was completelydried, the substrate was allowed to stand in an atmosphere of 90° C. for30 minutes and dried completely.

Next, in order to bond a substrate (color filter substrate) in which thespacer particles were located to an opposed array substrate, aperipheral sealing material was printed by a screen printing method, andboth substrates were bonded with this sealing material and then thesealing material was cured by heating at 160° C. for 90 minutes toproduce an empty cell with a cell gap of 5 μm. Then, a predeterminedamount of liquid crystal for a TN type was filled into the empty cell bya vacuum method, and after a filling port was sealed with an end-sealingmaterial, the end-sealing material was treated by heat at 120° C. for 30minutes to manufacture a TFT liquid crystal display.

Display quality of the TFT liquid crystal display obtained above wasevaluated. As a result, the existence of spacer particle was not foundin a pixel area and no defects of display such as light leakageresulting from abnormal orientation of liquid crystal in the vicinity ofthe spacer particle were found. Incidentally, the evaluation describedabove was conducted by visually observing the images magnified by anelectron microscope with a voltage of 4.2 V applied.

EXAMPLE 8

By following the same procedure as in Example 1 except for using thesubstrate B (color filter substrate) prepared in Example 7 as asubstrate for locating the spacer particles and ejecting the dispersionof spacer particles onto the exposed ITO surface (contact angle θarelative to the dispersion of spacer particles: 25°) in the form ofstripe on the substrate B (color filter substrate), a substrate B (colorfilter substrate) in which the spacer particles were located and a TFTliquid crystal display were manufactured.

Display quality of the obtained TFT liquid crystal display was evaluatedin the same manner as in Example 7. As a result, the existence of spacerparticle was not found in a pixel area and no defects of display such aslight leakage resulting from abnormal orientation of liquid crystal inthe vicinity of the spacer particle were found.

COMPARATIVE EXAMPLE 7

By following the same procedure as in Example 7 except for using thesubstrate C (color filter substrate) prepared in Example 7 as asubstrate for locating the spacer particles and ejecting the dispersionof spacer particles onto the surface (contact angle θb relative to thedispersion of spacer particles: 50°) of the orientation layer (polyimideresin) on the substrate C (color filter substrate), a substrate C (colorfilter substrate) in which the spacer particles were located and a TFTliquid crystal display were manufactured.

Display quality of the obtained TFT liquid crystal display was evaluatedin the same manner as in Example 7. As a result, the existence of somespacer particle was found around a pixel area and light leakageresulting from abnormal orientation of liquid crystal in the vicinity ofthe spacer particle was found.

Surface tension at 20° C. and dispersibility of the dispersions ofspacer particles prepared in Example 7 and 8 and Comparative Example 7,a property of locating spacer particle when the dispersion of spacerparticles is ejected onto the substrate, display quality as a liquidcrystal display, and purity of liquid crystal were evaluated in the samemanner as that described above. The results of evaluation were shown inTable 3. TABLE 3 Property of Purity of Surface locating liquid tensionspacer Display Display crystal (mN/m) Dispersibility particles quality(1) quality (2) (%) Example7 35 ⊚ ⊚ ◯ ⊚ 100 Example8 35 ⊚ ⊚ ◯ ⊚ 100Comparative 35 ⊚ ⊚ Δ ◯ 100 Example7

EXAMPLE 9

(1) Preparation of Spacer Seed Particle

To a separable flask, 15 parts by weight of divinylbenzene, 5 parts byweight of isooctyl acrylate and 1.3 parts by weight of benzoyl peroxideas an initiator were charged and mixed uniformly. Next, to this mixture,20 parts by weight of a 3% by weight aqueous solution of polyvinylalcohol (trade mark “KURARAY Poval GL-03” made by KURARAY CO., LTD.) and0.5 parts by weight of sodium dodecyl sulfate were charged and stirreduniformly, and then 140 parts by weight of ion-exchanged water wasadded. Then, this aqueous solution was polymerized at 80° C. for 15hours under nitrogen flow while being stirred to obtain fine particles.The obtained fine particles were adequately washed with hot water andacetone, and then classified and the acetone was volatilized to obtainspacer seed particles. An average particle diameter of the obtainedspacer seed particles was 5 μm and a CV value was 3.0%.

(2) Preparation of Spacer Particles

5 parts by weight of the obtained spacer seed particles was charged tomixed monomers comprising 20 parts by weight of dimethyl sulfoxide, 10parts by weight of hydroxy methacrylate, 8 parts by weight of i-butylmethacrylate and 2 parts by weight of methacrylic acid and dispersedwith a sonicater, and then the mixture was stirred uniformly. Next, areaction system was replaced with a nitrogen gas and the mixture wasstirred at 30° C. for 2 hours. Then, to the reaction system was added 10parts by weight of a 0.1 mol/liter aqueous solution of diammonium ceriumnitrate ([Ce(NH₄)₂] (NO₃)₆) regulated by a 1N aqueous solution of nitricacid, and after a polymerization reaction was conducted for 5 hours, areactant was taken out and separated into particles and a reactionsolution through filtration using a 3 μm membrane filter. The obtainedparticles were adequately washed with ethanol and acetone and then driedunder reduced pressure with a vacuum drier to obtain spacer particles(A), in which a vinyl-based thermoplastic resin is formed on the surfaceof the spacer seed particle by graft polymerization.

(3) Preparation of Medium

60 parts by weight of ethylene glycol, 20 parts by weight of isopropylalcohol and 20 parts by weight of ion-exchanged water were uniformlymixed and stirred to prepare a medium (a).

(4) Preparation of Spacer Dispersion

0.5 parts by weight of the spacer particles (A) was gradually added to100 parts by weight of medium (a), and uniformly mixed and stirred witha sonicater to prepare a dispersion of spacer.

(5) Evaluation

Surface tension at 20° C. and dispersibility of the dispersions ofspacer particles prepared in Examples 9 to 13 and Comparative Examples 8to 10, a property of locating spacer particle when the dispersion ofspacer particles is ejected onto the substrate, display quality as aliquid crystal display, and purity of liquid crystal were evaluated inthe same manner as that described above.

The results of evaluation were shown in Table 6.

EXAMPLES 10 to 13, COMPARATIVE EXAMPLES 8 to 10

By following the same procedure as in Example 9 except for changing thecomposition of the mixed monomers to the composition shown in Table 4, aspacer (B) to a spacer (D), in which a vinyl-based thermoplastic resinis formed on the surface of the spacer seed particle by graftpolymerization, were prepared.

And, mixed monomers comprising 10 parts by weight of hydroxyethylmethacrylate, 8 parts by weight of i-butyl methacrylate and 2 parts byweight of methacrylic acid was free radical polymerized in an ethylacetate solution, and then ethyl acetate was removed by drying underreduced pressure to yield a solid resin, and the solid resin was milledto obtain resin powder. Next, by using 2 parts by weight of the obtainedresin powder and 5 parts by weight of the spacer seed particle preparedin Example 9, and following the same manner as in Example 1 described inJapanese Kokai Publication 2000-347191, a spacer (E), in which a coatinglayer is formed on the surface of the spacer seed particle by shock wavepolymerization in high-velocity airflow, was prepared.

On the other hand, by following the same procedure as described aboveexcept for changing the composition of the medium to the compositionshown in Table 5, a medium (b) to a medium (d) were prepared.

By following the same procedure as in Example 9 except for changing acombination of a spacer and a medium to the combination shown in Table6, dispersions of spacer particles were prepared and subjected to anevaluation test.

The results of evaluation were shown in Table 6. TABLE 4 Spacerparticles A B C D E Spacer seed particles (part by weight) 5 5 5 5 5  Composition of Isobutyl methacrylate 8 14  2 4 0.8 mixed monomers Laurylmethacrylate — — — 4 — (part by weight) Methyl methacrylate — — — — —Hydroxyethyl methacrylate 10  6 18  10  1   Methacrylic acid 2 — — 2 0.2Dimethyl sulfoxide 20  20  20  20  — Preparation method Graft GraftGraft Graft Shock wave polymerization polymerization polymerizationpolymerization polymerization in high-velocity airflow

TABLE 5 Medium a b c d Composition Isopropyl alcohol 20 50 5 70 (part byweight) Ethylene glycol 60 — 40 — Ion-exchanged water 20 50 55 30Surface tension at 20° C. (mN/m) 35 27 53 23

TABLE 6 Dispersion of spacer Evaluation particles Property of Displayquality of Display quality of Purity of Spacer Surface tension locationspacer liquid crystal liquid crystal liquid particles Medium (mN/m)Dispersibility particles display cell (1) display cell (2) crystal (%)Example9 A a 35 ⊚ ⊚ ◯ ⊚ 100 Example10 B a 35 Δ ◯ Δ ◯ 100 Example11 C a35 ⊚ ⊚ ◯ ⊚ 100 Example12 D a 35 ◯ ◯ Δ ◯ 100 Example13 A b 27 ⊚ Δ Δ ◯ 100Comparative C c 53 ⊚ X Δ X 100 Example8 Comparative A d 23 Δ X X X 100Example9 Comparative E a 35 ⊚ ⊚ ◯ ⊚ 99.5 Example10

As is evident from Tables 4 to 6, the dispersions of spacer particles ofExamples 9 to 13 exhibited good or excellent performances with respectto all the dispersibility, the property of locating spacer particle, thedisplay quality of a liquid crystal display cell and the purity ofliquid crystal.

On the other hand, since the dispersion of spacer of Comparative Example8, in which the surface tension at 20° C. of the medium exceeded 50mN/m, and the dispersion of spacer of Comparative Example 9, in whichthe surface tension at 20° C. of the medium is less than 25 mN/m bothwere poor in the property of locating spacer on the substrate, thedisplay quality of a liquid crystal display cell thereof could not beevaluated. And, the dispersion of spacer of Comparative Example 10, inwhich the spacers prepared not by graft polymerization but by shock wavepolymerization in high-velocity airflow was used, had a low purity ofliquid crystal.

INDUSTRIAL APPLICABILITY

In accordance with the present invention, it is possible to provide themethod for manufacturing a liquid crystal display, the substrate for aliquid crystal display, the method for manufacturing the substrate for aliquid crystal display, and the dispersion of spacer particles, in whicha spacer particle can be precisely located at an arbitrary position on asubstrate by an ink-jet method.

1. A method for manufacturing a liquid crystal display, wherein spacerparticles are located at an arbitrary position on a substrate byejecting a dispersion of spacer particles by an ink-jet method, adiameter D₁ of an adhered droplet of said dispersion of spacerparticles, having adhered to said substrate, and a diameter D₂ of theadhering spacer particles, remaining after the said dispersion of spacerparticles is evaporated, satisfying a relationship of Equation (1).D ₂<(D ₁×0.5)  (1)
 2. The method for manufacturing a liquid crystaldisplay according to claim 1, wherein the surface temperature of asubstrate at the time when a dispersion of spacer particles adheres tothe substrate is at least 20° C. lower than a boiling point of a liquidhaving the lowest boiling point among liquids contained in saiddispersion of spacer particles.
 3. The method for manufacturing a liquidcrystal display according to claim 1, wherein the surface temperature ofa substrate at the time when a dispersion of spacer particles adheres tothe substrate is at least 20° C. lower than a boiling point of a liquidhaving the lowest boiling point among liquids contained in saiddispersion of spacer particles, and the surface temperature of asubstrate is 90° C. or less during a time period until the dispersion ofspacer particles is completely evaporated.
 4. The method formanufacturing a liquid crystal display according to claim 1, wherein adispersion of spacer particles comprises a medium containing a liquidhaving a boiling point of less than 100° C. in an amount of 10 to 80% byweight and spacer particles, and the content of said spacer particle is0.05 to 5% by weight.
 5. The method for manufacturing a liquid crystaldisplay according to claim 1, wherein a dispersion of spacer particlescomprises a medium containing a liquid having a boiling point of lessthan 100° C. in an amount of 10 to 80% by weight and a liquid having aboiling point of 150° C. or more in an amount of 80 to 10% by weight,and spacer particles, and the content of said spacer particle is 0.05 to5% by weight.
 6. The method for manufacturing a liquid crystal displayaccording to claim 1, wherein the dispersion of spacer particles has acontact angle of 25 to 70° relative to an orientation layer on asubstrate.
 7. A substrate for a liquid crystal display, wherein a colorfilter comprising a pixel area arrayed in accordance with a givenpattern and a shading area defining said pixel area is formed, anorientation layer, a contact angle of which relative to the dispersionof spacer particles is θb, being present in an area representing saidpixel area and, an area, a contact angle of which relative to thedispersion of spacer particles is θa, being present at least in a partof an area representing said shading area, and said θa and said θbsatisfying a relationship expressed by Equation (2).θa<θb  (2)
 8. A method for manufacturing the substrate for a liquidcrystal display according to claim 7, wherein after an orientationlayer, a contact angle of which relative to the dispersion of spacerparticles is θb, is uniformly formed on the whole surface of asubstrate, by applying non-contact energy irradiation to a position atwhich the spacer particle is chosen to be locate, the orientation layerin the position is removed or modified to bring a contact angle relativeto the dispersion of spacer particles into θa.
 9. A method formanufacturing the substrate for a liquid crystal display according toclaim 7, wherein a photosensitive polyimide resin precursor or aphotosensitive polyimide resin is uniformly applied to a substratehaving a surface, a contact angle of which relative to the dispersion ofspacer particles is θa, and by exposing the photosensitive polyimidefilm via the medium of a mask and developing the film, an orientationlayer comprising polyimide resin is formed in the form of a pattern onthe surface of the substrate other than the position at which the spacerparticle is chosen to be locate and a contact angle of the surface ofsaid orientation layer relative to the dispersion of spacer particles isbrought into θb.
 10. A method for manufacturing a liquid crystal displayusing the substrate for a liquid crystal display according to claim 7,wherein the dispersion of spacer particles is ejected onto the areawhere a contact angle of said substrate for a liquid crystal displayrelative to the dispersion of spacer particles is θa to locate thespacer particles.
 11. A dispersion of spacer particles, which comprisesspacer particles in which a vinyl-based thermoplastic resin, formed byfree radical polymerizing vinyl-based monomers having a hydrophilicfunctional group and/or an alkyl group having 3 to 22 carbon atoms, iscombined with the surface of an inorganic fine particle and/or anorganic fine particle by graft polymerization; and a medium comprisingwater and/or a hydrophilic organic solvent and having the surfacetension of 25 to 50 mN/m at 20° C., said spacer particles beingdispersed in the form of a single particle in said medium.
 12. Thedispersion of spacer particles according to claim 11, wherein thevinyl-based monomer contains a vinyl-based monomer having a hydrophilicfunctional group in an amount of 30 to 80% by weight and a vinyl-basedmonomer having an alkyl group having 3 to 22 carbon atoms in an amountof 20 to 60% by weight.
 13. The dispersion of spacer particles accordingto claim 11, wherein the hydrophilic functional group is at least onespecies selected from the group consisting of hydroxyl group, carboxylgroup, sulfonyl group, phosphonyl group, amino group, amide group, ethergroup, thiol group and thioether group.
 14. The method for manufacturinga liquid crystal display according to claim 2, wherein a dispersion ofspacer particles comprises a medium containing a liquid having a boilingpoint of less than 100° C. in an amount of 10 to 80% by weight andspacer particles, and the content of said spacer particle is 0.05 to 5%by weight.
 15. The method for manufacturing a liquid crystal displayaccording to claim 3, wherein a dispersion of spacer particles comprisesa medium containing a liquid having a boiling point of less than 100° C.in an amount of 10 to 80% by weight and spacer particles, and thecontent of said spacer particle is 0.05 to 5% by weight.
 16. The methodfor manufacturing a liquid crystal display according to claim 2, whereina dispersion of spacer particles comprises a medium containing a liquidhaving a boiling point of less than 100° C. in an amount of 10 to 80% byweight and a liquid having a boiling point of 150° C. or more in anamount of 80 to 10% by weight, and spacer particles, and the content ofsaid spacer particle is 0.05 to 5% by weight.
 17. The method formanufacturing a liquid crystal display according to claim 3, wherein adispersion of spacer particles comprises a medium containing a liquidhaving a boiling point of less than 100° C. in an amount of 10 to 80% byweight and a liquid having a boiling point of 150° C. or more in anamount of 80 to 10% by weight, and spacer particles, and the content ofsaid spacer particle is 0.05 to 5% by weight.
 18. The method formanufacturing a liquid crystal display according to claim 2, wherein thedispersion of spacer particles has a contact angle of 25 to 70° relativeto an orientation layer on a substrate.
 19. The method for manufacturinga liquid crystal display according to claim 3, wherein the dispersion ofspacer particles has a contact angle of 25 to 70° relative to anorientation layer on a substrate.
 20. The dispersion of spacer particlesaccording to claim 12, wherein the hydrophilic functional group is atleast one species selected from the group consisting of hydroxyl group,carboxyl group, sulfonyl group, phosphonyl group, amino group, amidegroup, ether group, thiol group and thioether group.